This is a sole-source procurement for 37 each of flight-critical NSN 1R-1560-011677486-VH, manufactured IAW reference number 70307-23903-103, with delivery FOB origin. The Government requires source approval before contract award and has solicited only previously approved sources because the technical data are not adequate for full and open competition. A non-approved source must submit the documentation required by the applicable NAVSUP WSS Source Approval Information Brochure with its proposal, and offers lacking required data will not be considered. The time normally required to approve a new source is such that award cannot be delayed pending approval, and award may proceed based on Fleet support needs if approval cannot be processed in time. Responsible sources may identify interest and capability or submit proposals, which the Government will use solely to determine whether to conduct a competitive procurement.