This notice is for a sole-source, flight-critical item (NSN 1R-6625-014793608-QE, ref 265-032-002) with a quantity of 20 units and delivery FOB origin. The technical data needed for competitive acquisition is unavailable or inadequate, so only sources previously approved by the Government have been solicited. Firms not already approved must submit the full source approval information detailed in the NAVSUP WSS brochure to be considered. The Government intends to negotiate with only one source under FAR 6.302-1, though all responsible sources may express interest or submit proposals. Award will be made only if the offeror, product, or manufacturer meets all qualification requirements at the time of award.