This procurement is for a flight-critical item requiring Government source approval prior to contract award; only previously approved sources have been solicited. Offerors must be approved sources or submit all required technical data detailed in the NAVSUP WSS Source Approval Information Brochures with their proposal, including an authorized distributor letter if applicable, or their offer will be deemed non-responsive and technically unacceptable. Alternative sources must qualify through Government-approved engineering procedures, and approval time is normally too long to delay award. The acquisition is conducted under emergency acquisition flexibilities, and past performance must be at an acceptable level as documented in SPRS/FAPIIS. No performance location or budget figure is specified in the description.