This procurement is for 4 units of a flight-critical NSN part (NSN 7R-1680-016586528-P8) requiring engineering source approval, with delivery FOB origin. Only sources previously approved by the Government have been solicited; new sources must submit detailed technical data per the NAVSUP WSS Source Approval Brochure to be considered. Offers that fail to provide all required source approval documentation will not be considered for award. Interested parties may identify their capability to supply the item as a commercial item within 15 days of this notice. The part is not being acquired under FAR Part 12, and no budget amount is specified.