48 C.F.R. §§ 52.247-61
As prescribed in 47.305-16(c), insert the following clause in solicitations and contracts when volume rates may apply:
F.o.b. Origin-Minimum Size of Shipments (APR 1984)
The Contractor agrees that shipment will be made in carload and truckload lots when the quantity to be delivered to any one destination in any delivery period pursuant to the contract schedule of deliveries is sufficient to constitute a carload or truckload shipment, except as may otherwise be permitted or directed in writing by the Contracting Officer. The agreed weight of a carload or truckload will be the highest applicable minimum weight which will result in the lowest freight rate (or per car charge) on file or published in common carrier tariffs or tenders as of date of shipment. In the event the total weight of any scheduled quantity to a destination is less than the highest carload/truckload minimum weight, the Contractor agrees to ship such scheduled quantity in one shipment. The Contractor shall be liable to the Government for any increased costs to the Government resulting from failure to comply with the above requirements. This liability shall not attach if supplies are outsized or of such nature that they cannot be loaded at the highest minimum weight bracket.
(End of clause)
48 C.F.R. §§52.247-61