48 C.F.R. § 216.203-4
(1) Generally, use the clauses at FAR 52.216-2, Economic Price Adjustment—Standard Supplies, FAR 52.216-3, Economic Price Adjustment—Semistandard Supplies, and FAR 52.216-4, Economic Price Adjustment—Labor and Material, only when—
[71 FR 39007, July 11, 2006]