Prescribed forms are not required to prepare solicitations described in this part. The following forms may be used at the discretion of the contracting officer: (a) Standard Form 33 , Solicitation, Offer and Award, and Optional Form 308 , Solicitation and Offer-Negotiated Acquisition, may be used to issue RFPs and RFIs. (b) Standard Form 30 , Amendment of Solicitation/ Modification of Contract, and Optional Form 309 , Amendment of Solicitation, may be used to amend solicitations of negotiated contracts. (c) Optional Form 17 , Offer Label, may be furnished with each request for proposal.View official source