48 C.F.R. § 13.403
13.403 Preparation and execution of orders.
Priced or unpriced contracts, purchase orders, or BPAs using the fast payment procedure shall include the following:
(a) A requirement that the supplies be shipped transportation or postage prepaid.
(b) A requirement that invoices be submitted directly to the finance or other office designated in the order, or in the case of unpriced purchase orders, to the contracting officer (see 13.302-2(c)).
(c) The following statement on the consignee's copy: