The requirement is for 43 EA of a flight-critical item under NSN 7R-5999-015241653-H1, with delivery FOB origin. The part requires engineering source approval by the design control activity because approved sources retain essential data rights, engineering knowledge, or technical data not economically available to the Government. Only previously approved sources have been solicited, and an alternate source must qualify under Government-approved procedures; approval timing generally cannot delay award. If not an approved source, the offeror must provide the NAVSUP WSS Source Approval Brochure information, and offers lacking required data will not be considered. The Government intends a sole-source action under FAR 6.302-1, but responsible sources may identify interest/capability, and award is contingent on meeting qualification requirements at award.