OT:RR:CTF:EMAIN H343580 JER
Center Director
Machinery Center of Excellence and Expertise
U.S. Customs and Border Protection
109 Shiloh Dr., Suite 300
Laredo, TX 78045
RE: Application for Further Review of Protest No. 3501-24-103378; Classification of a
Paint Sprayer Subassembly from China
ATTN: Timothy R. Huyett, Supervisory Import Specialist
Dear Center Director:
This is our decision regarding an Application for Further Review (“AFR”) of Protest
No. 3501-24-103378, filed on behalf of Wagner Spray Tech Corporation (“protestant”).
The Protest and AFR concern the classification of a certain paint sprayer subassembly from
China under the Harmonized Tariff Schedule of the United States (“HTSUS”). The AFR
was forwarded to this office for consideration.
Upon protestant’s request, U.S. Customs and Border Protection (“CBP”) met with
counsel on January 29, 2025, pursuant to 19 CFR § 177.4. Protestant then submitted a
supplemental filing on April 23, 2025. 1
FACTS:
The subject paint sprayer subassembly, Part No. 2425490, is the control box for the
Titan Impact X440, X540I, and X410 contractor paint sprayers. The subassembly consists
of a control board, insulator pad, and one panel of an aluminum die-cast housing. Installed
on the control board is a microcontroller unit, a fuse, a transformer, switches, and a voltage
1
Protestant has asked that certain information submitted in connection with this request be treated as confidential.
The request was clarified by counsel via email dated May 23, 2025. To the extent that this request conforms to the
requirements of 19 C.F.R. § 177.2(b)(7), the request for confidentiality is approved.
regulator. Wiring connects the control box subassembly to the system’s motor, gear box,
power switch, and to a transducer and potentiometer. The subassembly performs two
functions: (1) operating the paint sprayer’s motor based on other sprayer componentry; and
(2) dissipating heat to maintain an acceptable temperature within the sprayer and
specifically inside the control box. The subassembly is designed to receive inputs from the
sprayer’s internal sensors to ensure the motor’s speed achieves the user’s desired spray
pressure.
The heat dissipation function is performed by the insulator pad and the die-cast
housing, which absorbs and dissipates the heat generated by the control board at a consistent
rate to maintain a stable operating temperature. The subassembly’s rear housing
incorporates a series of eight fins, whose surface area assists in performing the heat
dissipation function. Each fin increases the surface area of the heat sink, which allows heat
dissipation by conduction and convection. The fins create surface area for thermal
conductivity on a small size block and are said to remove heat from electronic equipment.
According to protestant, the subassembly’s placement within the sprayer is critical, as the
sprayer’s motor will not operate properly and will overheat if improperly assembled. The
Titan Tool website indicates that the Titan Impact sprayer Models X440, X540I, and X410
each have eleven (11) air vents (or more) strategically placed near the motor, near the front
of the sprayer and control box area. 2
In its condition as imported, the subassembly is only composed of the basic,
inoperable control board, the insulator pad, and the rear panel of the die-cast housing. Any
additional assembly or programming occurs after importation in the United States.
The subject subassembly was entered between June 6, 2023, and February 11, 2024.
Some subassemblies were liquidated on July 29, 2024, under heading 9032, specifically
subheading 9032.89.60, HTSUS, which provides for “Automatic regulating or controlling
instruments and apparatus; parts and accessories thereof: Other instruments and apparatus:
Other: Other.” On August 16, 2024, other entries were liquidated under heading 8537, HTSUS,
specifically subheading 8537.10.91, HTSUS, which provides for “Boards, panels, consoles,
desks, cabinets and other bases, equipped with two or more apparatus of heading 8535 or 8536,
for electric control or the distribution of electricity, including those incorporating instruments or
apparatus of chapter 90, and numerical control apparatus, other than switching apparatus of
heading 8517: For voltage not exceeding 1,000 V: Other: Other.”
On November 19, 2024, Protestant filed the instant Protest and AFR. Protestant argues
the subassemblies are properly classified in heading 8424, HTSUS, specifically subheading
8424.90.90, HTSUS, which provides for: “Mechanical appliances (whether or not hand operated)
for projecting, dispersing or spraying liquids or powders; fire extinguishers, whether or not
charged; spray guns and similar appliances steam or sand blasting machines and similar jet
projecting machines; parts thereof: Parts: Other: Other.”
2
Titan Impact Electric Airless Sprayer, Titantool.com
https://www.titantool.com/catalogsearch/result/?q=+Titan+Impact+Electric+Airless+Sprayer
2
ISSUE:
Whether the subject subassemblies are properly classified under heading 8424, HTSUS,
heading 8537, HTSUS, or heading 9032, HTSUS.
LAW AND ANALYSIS:
A decision on classification and the rate and amount of duties chargeable is a protestable
matter under 19 U.S.C. §1514(a)(2). The subject Protest was timely filed on November 19, 2024,
within 180 days of liquidation of each entry, pursuant to 19 U.S.C. § 1514(c)(3). Further Review
of Protest No. 3501-24-103378 is properly accorded pursuant to 19 CFR § 174.24(a), as the
decision against which the protest was filed is alleged to be inconsistent with a CBP ruling or
decision with respect to the same or substantially similar merchandise. In support for its AFR
under 19 CFR § 174.24(a), protestant cites to CBP Headquarters Ruling Letters (“HQ”) 959467,
dated October 9, 1996, where CBP classified an “electromechanical device for securing an
automobile door,” under heading 8708, HTSUS, because, although it was principally comprised
of a board of heading 8537, HTSUS, it also incorporated a rubber-coated steel housing that,
protestant asserts, performed a “significant additional function.”
Classification under the HTSUS is in accordance with the General Rules of Interpretation
(GRIs). GRI 1 provides that the classification of goods is determined according to the terms of
the headings of the tariff schedule and any relative section or chapter notes. In the event goods
cannot be classified solely on the basis of GRI 1, and if the headings and legal notes do not
otherwise require, the remaining GRIs 2 through 6 will then be applied in order.
The HTSUS headings under consideration are as follows:
8424 Mechanical appliances (whether or not hand operated) for projecting, dispersing or
spraying liquids or powders; fire extinguishers, whether or not charged; spray guns and
similar appliances steam or sand blasting machines and similar jet projecting machines;
parts thereof:
* * *
8537 Boards, panels, consoles, desks, cabinets and other bases, equipped with two or more
apparatus of heading 8535 or 8536, for electric control or the distribution of electricity,
including those incorporating instruments or apparatus of chapter 90, and numerical
control apparatus, other than switching apparatus of heading 8517:
* * *
9032 Automatic regulating or controlling instruments and apparatus; parts and accessories
thereof:
Note 2 to Section XVI, HTSUS, in relevant part, provides:
2. Subject to note 1 to this section, note 1 to chapter 84 and to note 1 to chapter 85, parts of machines
(not being parts of the articles of heading 8484, 8544, 8545, 8546 or 8547) are to be classified
according to the following rules:
3
(a) Parts which are goods included in any of the headings of chapter 84 or 85 (other than headings
8409, 8431, 8448, 8466, 8473, 8487, 8503, 8522, 8529, 8538 and 8548) are in all cases to be
classified in their respective headings.
(b) Other parts, if suitable for use solely or principally with a particular kind of machine, or with a
number of machines of the same heading (including a machine of heading 8479 or 8543) are to
be classified with the machines of that kind or in heading 8409, 8431, 8448, 8466, 8473, 8503,
8522, 8529 or 8538 as appropriate. However, parts which are equally suitable for use principally
with the goods of headings 8517 and 8525 to 8528 are to be classified in heading 8517, and
parts which are suitable for use solely or principally with the goods of heading 8524 are to be
classified in heading 8529….
Note 7(a) to Chapter 90, HTSUS, states heading 9032, HTSUS, applies to:
Instruments and apparatus for automatically controlling the flow, level, pressure or other variables
of liquids or gases, or for automatically controlling temperature, whether or not their operation
depends on an electrical phenomenon which varies according to the factor to be automatically
controlled, which are designed to bring this factor to, and maintain it at, a desired value, stabilized
against disturbances, by constantly or periodically measuring its actual value
The Explanatory Notes (ENs) to the Harmonized Commodity Description and
Coding System represent the official interpretation of the tariff at the international level.
While neither legally binding nor dispositive, the ENs provide a commentary on the scope
of each heading of the HTSUS and are generally indicative of the proper interpretation of
these headings. See T.D. 89-80, 54 Fed. Reg. 35127, 35128 (August 23, 1989). EN 90.32
provides that:
Automatic control apparatus for liquids or gases and apparatus for automatically controlling
temperature form part of complete automatic control systems and consist essentially of the
following devices:
(A) A device for measuring the variable to be controlled (pressure or level in a tank, temperature in
a room, etc.); in some cases, a simple device which is sensitive to changes in the variable (metal or
bi-metal rod, chamber or bellows containing an expanding liquid, float, etc.) may be used instead of
a measuring device.
(B) A control device which compares the measured value with the desired value and actuates the
device described in (C) below accordingly.
(C) A starting, stopping or operating device.
Protestant argues that the subject control box subassembly is not classified under heading
9032, HTSUS, because the subassembly control box is not designed to measure a variable and
bring that variable back into a fixed parameter as required by Note 7(a) to Chapter 90, HTSUS.
Protestant further asserts that because the subassembly consists of a heat sink and performs a
heat dissipation function, that it is beyond the scope of heading 8537, HTSUS. Specifically,
protest alleges that the subassembly “incorporates critical aluminum and thermal conductor
properties” that perform a mechanical function which goes beyond the definition of heading
8537, HTSUS.” Instead, protestant contends that the subassembly is classified under heading
8424, HTSUS, as a part of the Titan Impact paint sprayer.
4
Given that Note 1(m) to Section XVI, HTSUS, excludes articles of Chapter 90, HTSUS,
the initial determination is whether the subassembly is classifiable under heading 9032, HTSUS.
Classification under heading 9032, HTSUS, Note 7(a) to Chapter 90, HTSUS, requires the
subject subassembly to automatically control the pressure of the paint sprayer and maintain its
desired pressure by constantly or periodically measuring its actual value. Moreover, EN 90.32
explains, in relevant part, that instruments and apparatus of heading 9032, HTSUS, consist
essentially of, “(B) A control device which compares the measured value with the desired value
and actuates the device described in (C) below accordingly and (C) A starting, stopping or
operating device.”
To be classified in heading 9032, HTSUS, the subject control box assembly must have
the capacity to perform the requisite functions described by the terms of Note 7(a) to Ch. 90,
HTSUS. The subject control box subassembly consists of three components, (1) a control board
Printed Circuit Board Assembly (“PCBA”) 3, (2) a die-cast aluminum housing and (3) an
insulator pad (described by the importer as a “thermal conductor”). Onboarded onto the control
board PCBA 4 is a microcontroller unit 5 (“MCU”), a fuse, a transformer, switches, and a voltage
regulator. The control board and all its installations along with the insulator pad are located
inside the die-cast aluminum housing. Wiring assemblies connect the control box subassembly
and its control board and MCU to the system’s motor, gear box and power switch. The
transducer and potentiometer are connected to the PCB by wire-to-board connectors.
Based on the facts provided, the subassembly is precluded from classification under
heading 9032, HTSUS, because it does not satisfy the requirements of Note 7(a) to Chapter 90,
HTSUS. Specifically, it does not contain a measuring device to measure the sprayer pressure of
the Titan Impact paint sprayer. Secondly, it does not contain a device that compares the
measured value with the desired value. Lastly, the subassembly does not bring that value back to
a desired value. Although it functions as an electrical control and distribution apparatus, the
facts establish that the control box subassembly does not contain a sensor, meter or other
measuring device. Therefore, it does not have the capacity to measure the sprayer pressure and
bring the pressure back to a fixed level. Instead, the act of monitoring and measuring the
system’s paint pressure is performed by other internal circuitry. One of these components acts
as a sensor to detect and thereby measures the pressure inside the sprayer system. Likewise, a
variable resistor is programed to measure the user’s desired spray pressure. The subassembly
uses the input from both of these internal components to operate the motor speed of the sprayer.
Hence, the subassembly itself does not measure the pressure inside the paint sprayer and as such
cannot be classified in heading 9032, HTSUS. See Belimo Automation A.G. v. United States,
3
Generally speaking, a printed circuit board is an electronic assembly that uses conductors to create electrical
connections between components. See https://resources.altium.com/p/what-is-a-pcb (last visited December 12,
2025).
4
Control Board (a type of PCBA) A control board is a fully functional, assembled PCB that contains electronic
components like microprocessors, memory, and other integrated circuits. Its purpose is to manage, regulate, and
direct the behavior of other components or systems. A PCB is also said to be a structure for assembling electronic
components and their connections into a unified circuit that allows electrical current to pass between components.
See https://www.techtarget.com/whatis/definition/printed-circuit-board-PCB (last visited December 12, 2025).
5
An MCU is a self-contained computer on a single integrated circuit, that generally features a processor, memory,
and programmable input/output peripherals designed for specific control tasks within an embedded system. See
https://www.ibm.com/think/topics/microcontroller (last visited December 12, 2025).
5
774 F.3d 1362, (Fed. Cir. 2014) (holding that the merchandise could not be classified in heading
9032, HTSUS, because it was “not designed to measure the actual value of a factor of liquids or
gases,” pursuant to Note 7(a) to Chapter 90, HTSUS).
Finding that the subject control box assembly is not classified in heading 9032, HTSUS,
is consistent with previous CBP rulings involving substantially similar control box assemblies.
For instance, in HQ H328055, dated July 31, 2023, 6 CBP addressed whether a control box
assembly was classifiable in heading 9032, HTSUS, as an automatic regulating or controlling
apparatus or in heading 8481, HTSUS, as a pressure reducing valve. In that decision CBP stated
that “in order for the control box to be classified in heading 9032, HTSUS, it would have to
constantly monitor the hydraulic fuel pressure and then keep that pressure within a certain
predetermined set of parameters.” The control box in HQ H328055 did not perform that
function. Instead, it adjusted the hydraulic fluid pressure based on the information received from
the pressure sensor and brake pressure from the driver pressing the brake pedal. As such, it was
not classifiable under heading 9032, HTSUS.
Similarly, in HQ 967440, dated November 23, 2005, CBP classified an electronic
controller board for a household washing machine in 8537 rather than 9032, HTSUS, because the
electronic controller board only had the capacity to distribute electricity. In ruling out heading
9032, HTSUS, the decision in HQ 967440 noted that the electronic controller board did not
control the torque variation value, as it did not measure the torque variation value against its
actual value and like the subject control box subassembly, did not bring the torque variation back
to the desired level. Like the control box assembly in HQ H328055 and the electronic controller
board in HQ 967440, the subject control box assembly does not itself have the capacity (i.e. it
does not have a sensor or meter) to measure the spray pressure but instead must rely on signals
sent from the transducer and potentiometer to control the motor speed and pressure of the paint
sprayer. Compare HQ 965948, dated January 27, 2003. 7
Next, we acknowledge that the protestant argues that the instant subassembly is
classifiable as a part in heading 8424, HTSUS. Classification as a part requires that the
subassembly be solely or principally designed for use with Titan Impact paint sprayers. See Note
2(b) to Section XVI, HTSUS, (which states, in pertinent part, “Other parts, if suitable for use
solely or principally with a particular kind of machine…are to be classified with the machines of
that kind.”
However, before classification can be determined pursuant to Note 2(b), classification
pursuant to Note 2(a) to Section XVI, HTSUS, must be examined first. With regard to the
6
The control box assembly in H328055 controlled brakes by utilizing pressure sensor signals and pedal stroke
sensor signals. The pressure sensors detected the pressure level and relayed the signal to the control box assembly
which then controlled the brakes.
7
By contrast, in HQ 965948, dated January 27, 2003, classified a Refrigerator Control Box in heading in 9032,
HTSUS, rather than 8537, HTSUS, because CBP determined that the principal use of the control box was imparted
by two thermostats contained inside the control box. The thermostats upon measuring the temperature transmitted
signals to the defrost timer which in turn transmitted signals to the control box triggering the defrosting operation
thereby allowing the control box to control the defrost cycle. The decision in HQ 965948 reasoned that the principal
use of the refrigerator control box was the measuring, maintaining, and establishment of temperatures, i.e., functions
described in heading 9032, HTSUS.
6
application of Note 2 to Section XVI, HTSUS, CBP has long held that regardless of whether
goods are prima facie classifiable as a part or accessory of chapters 84 or 85, HTSUS, such
goods are to be classified in their own respective headings pursuant to Note 2(a). For example,
in HQ H179956, dated July 31, 2013, CBP addressed the classification of unassembled paint
spray gun kits and the individual parts thereof. CBP determined that control boards for the paint
spray gun kits were intended to be primarily used with that particular paint spray gun. However,
CBP classified the control boards in heading 8537, rather than as a part in heading 8424,
HTSUS, by operation of Note 2(a) to Section XVI. Likewise, in HQ 966787, dated February 9,
2004, CBP considered the classification of a fan shroud assembly that was solely used with an
automatic data processing (“ADP”) machine of heading 8471, HTSUS. In HQ 966787, CBP
noted that Note 2(b) could not be applied if the fan shroud assembly was classifiable in its own
heading. The decision in HQ 966787 determined that the fan shroud assembly was classified as
a fan under heading 8414, HTSUS, pursuant to Note 2(a) to Section XVI, rather than as a part of
the ADP machine. Accordingly, if it is determined that the subject control box subassembly is
provided for in any of the eligible headings of chapter 84 or 85, HTSUS, then it must be
classified in its own respective heading pursuant to Note 2(a) to Section XVI, HTSUS.
Under our facts, the construction, design and functionality of the Titan control box
subassembly indicates that this product is described by the terms of heading 8537, HTSUS.
First, the control box constitutes a board, panel or base for purposes of heading 8537, HTSUS, as
it is a housing that is equipped with two or more apparatus of heading 8536, HTSUS, namely, the
printed circuit board assembly and the microcontroller unit. The subassembly, described as the
“control box, rear NG440”, is capable of electrical control and the distribution of electrical
currents. It is on-boarded by several installations which are described eo nomine in EN 85.37
(i.e., switches, a transformer, a voltage regulator, and a fuse). More importantly, the primary
function of the control box subassembly is to control the electric motor of the paint sprayer.
Incorporated within the control box subassembly is a microcontroller unit (“MCU”) that
activates the circuit that turns on the motor. To operate the sprayer, the user pulls the gun trigger
and pressure in the system drops. After the system drops to a designated level, the MCU in the
subassembly turns on the circuit that then turns on the motor. The motor, in turn, drives the
pump through the gearbox which results in the actual movement and speed of the motor. Here,
the capacity of the control board to receive, process and send electrical signals which controls the
electric motor is a function described by heading 8537, HTSUS. Specifically, the control of the
electrical current that activates the motor is a function described by the terms of heading 8537,
HTSUS, as is the MCU activation that turns the motor on and off. Accordingly, we find that the
subject control box subassembly is described by the terms of heading 8537, HTSUS. See
generally, HQ 959022, dated June 18, 1996 (Where a PCB was classified in heading 8537,
HTSUS), and HQ 959474, dated September 27, 1996 (Where CBP classified a “switchplate”
assembly Part #16674877 in heading 8537, HTSUS, rather than as a part of heading 8708,
HTSUS).
However, protestant contends that the heat dissipation function precludes the subject
control box subassembly from classification under 8537, HTSUS. According to protestant, the
secondary function of the control box PCBA is to dissipate heat. Protestant states that this
function is accomplished through thermal conduction created by a combination of an insulator
pad, eight heat sink fins and an aluminum housing. Protestant states that the insulator pad and
7
the heat sink fins “serve to draw heat away from the control board and then dissipate the heat at a
consistent rate so as to maintain a stable temperature.” Protestant adds that, without the heat
dissipation, the paint sprayer would not function properly. Protestant thus argues that the heat
dissipation function constitutes a function that is beyond the scope of heading 8537, HTSUS.
In support of its assertion, protestant cites to HQ 959474, dated September 27, 1996,
where CBP determined that switchplate assemblies were classified as motor vehicle parts rather
than as an electrical control board because they incorporated louvered grilles with a mechanical
component that performed significant additional functions which were outside the purview of
8537, HTSUS. In HQ 959474, the front door switchplate assembly was designed to be
incorporated into the driver’s side armrest on the door and included a louvered air conditioning
and heating grille, a lockout feature and window up/down components. The louvered grille had
a finger-operated control wheel that adjusted an aperture to allow heat and coolness to enter.
Each of the 4 window buttons had a switch that closed an electrical circuit, closing the circuit
activated a motor which raised or lowered the window. CBP noted that Parts #16674833 and
16674834 incorporated combinations of window up/down and lockout switches as well as
temperature dial switches. Hence, HQ 959474 concluded that the mechanical function of the
louvered grille performed a function that was beyond the scope of heading 8537, HTSUS.
Similarly, protestant notes that in HQ 959467 dated October 9, 1996, CBP classified an
electromechanical device in heading 8708, HTSUS, as a part rather than as a control board of
8537, HTSUS. In HQ 959467, because of its construction and placement connecting one
electrical component to the other, a rubber-coated steel housing facilitated the electromechanical
interaction between a component located inside the door latch and a switch located inside the
steel housing causing the door to remain closed while the car was in motion. CBP determined
that the mechanical interaction between the door latch component and the switch of keeping a
car door locked while the car was in motion was an additional function outside the purview of
heading 8537, HTSUS. The subject control box assembly possesses no such significant or
additional function.
Instead, heat dissipation and thermal management are common features of electronic
devices. 8 Our research indicates that heat sinks attached to printed circuit board components,
CPUs, power transistors and switches are essential for ensuring the longevity and functionality of
PCBs and their components. 9 Protestant offers the following definition of a heat sink, “a heat
sink is defined as ‘a finished good made of extruded aluminum that cools a solid material,
principally electronics and computer equipment (servers, laptops, etc.), by transferring the heat
generated in such devices to a fluid medium, such as air or a liquid.” 10 In HQ 966787, CBP
noted that “a heat sink is a protective device that absorbs and dissipates the excess heat generated
by an electronic system.” HQ 966787 continued, “[a heat sink] generally incorporates a piece of
thermally conductive metal that radiates heat away from an electronic device, in concert with a
fan, to prevent it from overheating.”
8
Heat Sink PCB, Millenium Circuits Limited. https://www.mclpcb.com/blog/heat-sink-pcb/ (last visited December
12, 2025).
9
Id.
10
Wagner Spray Tech Corporation v. United States & Aluminum Extrusions Fair Trade Committee, Slip Op. 25-49,
at 22 (Ct. Int'l Trade, Apr. 21, 2025).
8
CBP has previously classified PCBs and electronic control boards consisting of heat sinks
in heading 8537, HTSUS, and other headings of chapters 84 and 85, despite this additional
function. For example, in HQ 967440, CBP classified an electronic control board under heading
8537, HTSUS, that featured a heat sink. The electronic control board in HQ 967440 was
surrounded by metal which acted as a heat sink for the board. The control board in HQ 967440
controlled all the functions necessary to operate a washing machine including stopping and
starting the motor. Yet, because its primary purpose was the electrical control of the motor the
presence and mechanical function of the heat sink did not preclude its classification under
heading 8537, HTSUS. Likewise, in HQ 965434, dated February 11, 2002, CBP classified a
PCB component of a control unit with a heat seal mounted directly onto it in heading 8537,
HTSUS. Similarly, a fan shroud assembly in HQ 966787 featuring a heat sink on-boarded onto
its PCB was classified pursuant to Note 2(a) rather than Note 2(b) to Section XVI, HTSUS,
because CBP determined that classification in its own heading was more appropriate than
classification as a part.
Additionally, in NY I84724, dated August 19, 2002, a network interface module (“NIM”)
was classified as an electrical apparatus of 8517, HTSUS, despite the presence and function of a
heat sink. The NIM in NY I84724 contained three printed circuit board subassemblies and
consisted of a heat sink at the rear of the module to perform the heat dissipation function.
Similar to the subject control box subassembly, the NIM was housed in a metal case with various
connectors used to provide electrical and power interfaces for the operation of an optical
communication system. In NY I84724, neither the heat sink nor the metal housing altered the
classification of the NIM for purposes of Note 2(a) to Section XVI, HTSUS.
In the instant case, although heat dissipation is essential to the performance of the subject
control box subassembly, heat dissipation is a supportive function that is ancillary to its primary
purpose. The primary purpose of the subject control box assembly is to operate the motor of the
paint sprayer. Unlike the refrigerator control box in HQ 965948, temperature control is not the
primary purpose of the subject control box assembly. Additionally, nothing in the facts suggest
that the heat sink fins and insulator pad directly impact the temperature of the entire paint sprayer
or that their heat dissipation capacity extends beyond the control box area. Instead, our research
indicates that the Titan Impact sprayer Models X440, X540I, and X410 each have at least eleven
(11) air vents strategically placed near the motor and control box area 11 to facilitate air
circulation.
Contrary to protestant’s assertions, the subject heat sink fins, aluminum housing and
insulator pad do not constitute a “heat sink assembly.” Unlike the subject heat sink fins, heat
sink assemblies ensure aggressive heat transfer for electronic processing units and other
components. See, NY N111277, dated July 8, 2010 (Which classified a heat sink assembly in
heading 8473, HTSUS). They are typically comprised of a radiator, cooling fan, pump, liquid
cooling solution and an interposer plate. Id. Other heat sink assemblies are comprised of an
aluminum radiator, cooling fan, pump, and copper coldplate. See generally, NY N102598, dated
May 3, 2010; see also, NY N336939, dated December 20, 2023 (Where a heat sink assembly
11
Titan Impact Electric Airless Sprayer, Titantool.com
https://www.titantool.com/catalogsearch/result/?q=+Titan+Impact+Electric+Airless+Sprayer (last visited
December 12, 2025).
9
comprised of aluminum radiator, a copper block, three LED lighted fans, and a pump was
classified in heading 8473, HTSUS). In NY J86335, dated July 15, 2003, CBP noted that, in
response to “today’s standards, heat sinks have been replaced by (heat sink) assemblies that have
become proportionately larger and more complex in design.” As such, heat sink assemblies like
those mentioned in NY J86335, NY N111277, NY N102598 and NY N336939 have the capacity
to absorb heat, provide directional air flow, disperse heat by a radiator and fan combination and
thereby ensure the necessary heat transfer. None of these traits or mechanical functions are
present in the instant case.
Based on the information provided, we conclude the heat sink fins, aluminum housing
and insulator pad are only capable of drawing heat away from the control board and do not have
the capacity to provide direct thermal management to the motor or the paint sprayer. Although
alleviating hot temperatures inside the control box indirectly impacts the temperature of the
sprayer, this function is not the functional equivalent of a heat sink assembly (NY N336939) or
the temperature control performed by a thermostat (HQ 965948). Hence, we do not agree that
the mechanical function of the heat sink fins, aluminum housing and insulator pad constitute an
additional function so significant as to remove the subject control box assemblies from the
parameters of heading 8537, HTSUS. Accordingly, we find that the subject control box is
classified in heading 8537, HTSUS.
HOLDING:
By application of GRIs 1 (Note 2(a) to Section XVI) and 6, the Control Box Subassembly
is classified in heading 8537, HTSUS, specifically subheading 8537.10.91, HTSUS, which
provides for: “Boards, panels, consoles, desks, cabinets and other bases, equipped with two or
more apparatus of heading 8535 or 8536, for electric control or the distribution of electricity,
including those incorporating instruments or apparatus of chapter 90, and numerical control
apparatus, other than switching apparatus of heading 8517: For a voltage not exceeding 1,000V:
Other: Other: Other.” The general, column one rate of duty is 2.7 percent ad valorem.
Pursuant to U.S. Note 20 to Subchapter III, Chapter 99, HTSUS, products of China
classified under subheading 8537.10.91, HTSUS, unless specifically excluded, are subject to an
additional 25 percent ad valorem rate of duty under secondary tariff number 9903.88.03,
HTSUS, pursuant to Section 301 of the Trade Act of 1974.
This ruling does not address the applicability of any additional duties that may apply to
the goods discussed herein. Likewise, duty rates are provided for your convenience and are
subject to change. The text of the most recent HTSUS and the accompanying duty rates are
provided at www.usitc.gov.
You are instructed to DENY the Protest.
You are instructed to notify the protestant of this decision no later than 60 days from the
date of this decision. Any reliquidation of the entry or entries in accordance with the decision
must be accomplished prior to this notification. Sixty days from the date of the decision, the
Office of Trade, Regulations and Rulings will make the decision available to CBP personnel and
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the public on the Customs Rulings Online Search System (CROSS) at https://rulings.cbp.gov/, or
other methods of public distribution.
Sincerely,
for Yuliya A. Gulis, Director
Commercial and Trade Facilitation Division
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