OT:RR:NC:N1:105
Chi Hwan Choi
3AC Co., Ltd.
1301, 181, Gasan digital 1-ro, Geumcheon-gu
Seoul
South Korea
RE: The country of origin of an air filter
Dear Mr. Choi:
In your letter dated November 28, 2025, you requested a country of origin ruling on an air filter. Descriptive
literature was provided for our review.
The item under consideration is described as a 3AC deodorizing filter, which is a replacement filter that is
inserted into an air purifier and removes odors from the air. Specifically, the motor inside the air purifier
draws external air into the device, forcing it to pass through the deodorizing filter. During this process,
odor-causing particles are captured by the impregnated activated carbon contained within the filter. The
purified air is then released back into the environment, creating a cleaner atmosphere.
The Korean components include the injection core and the mesh, while the activated carbon comes from
China. The deodorization pad and polyethylene bag can be sourced from various countries. The production
process begins with the production of the activated carbon (crude coal) in China. The process then moves to
South Korea, where the deodorizing filter injection core and hexagonal mesh are fused together with a heat
press. The next step is the primary trimming, which includes cutting of the fused mesh to match the
dimensions of the injection-molding. Then, the activated carbon filling process occurs, which involves
uniformly filling each core cell. Next, is the secondary heat pressing where the hexagonal mesh is fused onto
the opposite side of the carbon-filled product. Then, the secondary trimming finishes the product to match the
injection-molded core dimensions. Finally, a visual inspection (checking appearance and verifying fusion
defects such as mesh tearing) is completed followed by packaging and delivery.
When determining the country of origin, the substantial transformation analysis is applicable. See, e.g.,
Headquarters Ruling Letter H301619, dated November 6, 2018. The test for determining whether a
substantial transformation will occur is whether an article emerges from a process with a new name,
character, or use different from that possessed by the article prior to processing. See Texas Instruments Inc. v.
United States, 681 F.2d 778 (C.C.P.A. 1982). This determination is based on the totality of the evidence. See
National Hand Tool Corp. v. United States, 16 C.I.T. 308 (1992), aff’d, 989 F.2d 1201 (Fed. Cir. 1993).
Regarding the origin of the deodorizing filter, it is our opinion that the manufacturing and assembly process
performed in South Korea transforms the Chinese activated carbon into a finished air filter. This
transformation results in a finished product substantially different than that of the general-purpose raw
material. While the activated carbon is performing a key function, it is not until the powder is added to the
filtering cartridge that it can perform the function of filtering air. Essentially, there is no way for the activated
carbon on its own to work with the air purifier to filter the air until it is prepared in the proper form.
Therefore, in our opinion, the country of origin of the deodorization filter is South Korea, which is where the
filter is manufactured.
The holding set forth above applies only to the specific factual situation and merchandise description as
identified in the ruling request. This position is clearly set forth in Title 19, Code of Federal Regulations
(CFR), Section 177.9(b)(1). This section states that a ruling letter is issued on the assumption that all of the
information furnished in the ruling letter, whether directly, by reference, or by implication, is accurate and
complete in every material respect. In the event that the facts are modified in any way, or if the goods do not
conform to these facts at time of importation, you should bring this to the attention of U.S. Customs and
Border Protection (CBP) and submit a request for a new ruling in accordance with 19 CFR 177.2.
Additionally, we note that the material facts described in the foregoing ruling may be subject to periodic
verification by CBP.
This ruling is being issued under the provisions of Part 177 of the Customs and Border Protection
Regulations (19 C.F.R. 177).
A copy of the ruling or the control number indicated above should be provided with the entry documents
filed at the time this merchandise is imported. If you have any questions regarding the ruling, please contact
National Import Specialist Jason Christie at [email protected].
Sincerely,
(for)
Evan Conceicao
Designated Official Performing the Duties of the Division Director
National Commodity Specialist Division