48 C.F.R. § 46.304

The contracting officer shall insert the clause at 52.246-4, Inspection of Services—Fixed-Price, in solicitations and contracts for services, or supplies that involve the furnishing of services, when a fixed-price contract is contemplated and the contract amount is expected to exceed the simplified acquisition threshold. The contracting officer may insert the clause in such solicitations and contracts when the contract amount is expected to be at or below the simplified acquisition threshold and inclusion is in the Government's interest.