This opportunity is for the procurement of 4 units of a flight-critical, commercial-off-the-shelf item (NSN 0R-2840-015435920-CL). Delivery is FOB Origin, and the item requires Government source approval prior to award, as technical data is not adequate for full competition. Only previously approved sources have been solicited; new sources must submit detailed information per the NAVSUP WSS Source Approval Brochure with their proposal. The Government intends to solicit and negotiate with only one source under FAR 6.302-1, but all responsible sources may submit proposals. Proposals will be considered if received within 45 days of this synopsis publication.