As used in this subpart:
Order-level materials means supplies and/or services acquired in direct support of an individual task or delivery order placed against an authorized (see GSAR 538.7201(b) Federal Supply Schedule (FSS) contract or FSS Blanket Purchase Agreement (BPA)), when the supplies and/or services are not known at the time of Schedule contract or FSS BPA award. The prices of order-level materials are not established in the FSS contract or FSS BPA. However, order-level materials are purchased under the authority of the FSS program, pursuant to 41 U.S.C. 152(3) , and are not open market items, which are discussed in FAR 8.402(f).
48 C.F.R. §538.7200