This is a sole-source opportunity for 4 units of a flight-critical, source-controlled item (NSN 1R-5985-015612380-E7, ref 123SCAV9119-21), with delivery required FOB origin. The part must be acquired from or repaired by a government-approved source, as the technical data and data rights are not available to support competition or qualification of alternate sources. Only sources already approved by the government have been solicited, and award cannot be delayed for new source approval. Interested parties that are not approved sources may respond, but must submit the required Source Approval Brochure information with their proposal or document prior submission; offers failing to do so will not be considered. This notice is not a request for competitive proposals, and award will only be made to an offeror meeting qualification requirements at the time of award.