As used in this subpart—

(a) Exchange (trade-in) property means property which—

(1) Is not excess but is eligible for replacement (because of obsolescence, unserviceability, or other reason); and

(2) Is applied as whole or partial payment toward the acquisition of similar items (i.e., items designed and constructed for the same purpose).

(b) Property means items that fall within one of the generic categories listed in DoD Manual 4140.01, Volume 9, DoD Supply Chain Materiel Management Procedures: Materiel Programs.