This procurement is for 16 units of a safety relief valve (NSN 4820016191363), with delivery required within 165 days after order. The approved sources are specified by two manufacturer part numbers. The solicitation is a Request for Quote (RFQ) available only online, with no hard copies, specifications, or drawings provided. Quotes must be submitted electronically, and all responsible sources are encouraged to respond. No budget amount or performance location is specified.