; and (ii) means in the form of mill product, such as bar, billet, wire, slab, plate or sheet, and in the grade appropriate for the production of— (I) a finished end item delivered to the executive agency; or (II) a finished component assembled into an end item delivered to the executive agency. (E) The term commercially available off-the-shelf has the meaning provided in section 104 of this title. (F) The term assemblies means items forming a portion of a system or subsystem that can be provisioned and replaced as an entity and which incorporates multiple, replaceable parts. (G) The term commercial derivative military article means an item procured by the Department of Defense that is or will be produced using the same production facilities, a common supply chain, and the same or similar production processes that are used for the production of articles predominantly used by the general public or by nongovernmental entities for purposes other than governmental purposes. (H) The term subsystem means a functional grouping of items that combine to perform a major function within an end item, such as electrical power, attitude control, and propulsion. (I) The term end item means the final production product when assembled or completed, and ready for issue, delivery, or deployment. (J) The term subcontract includes a subcontract at any tier. (c) Use of United States steel, iron, aluminum, and manufactured products (1) In general The head of an executive agency may not enter into a contract related to the construction of a vessel unless the steel, iron, aluminum, and manufactured products to be used in the construction of the vessel are produced in the United States. (2) Exceptions The provisions of paragraph (1) shall not apply where the head of an executive agency finds— (A) that their application would be inconsistent with the public interest; (B) that such materials and products are not produced in the United States in sufficient and reasonably available quantities and of a satisfactory quality