This is a sole-source procurement for six each of a flight-critical part, with delivery FOB origin. The item requires Government source approval by the design control activity, and only previously approved sources have been solicited. Because the approved source(s) retain essential data rights or manufacturing/repair knowledge not economically available to the Government, the Government intends to solicit and negotiate with only one source under FAR 6.302-1. A non-approved source must submit the source-approval information described in the applicable NAVSUP WSS brochure with its proposal; offers lacking required data or prior submission documentation will not be considered for award. No drawings are available, and FAR Part 12 commercial-item procedures are not being used.