The Department of Defense, specifically the Department of the Navy through NAVSUP Weapon Systems Support, is seeking proposals for the repair and modification of embedded GPS-inertial navigation systems, identified by NSN 7R-6605-016155547-KB. This procurement involves a quantity of four units and requires government source approval prior to contract award due to the flight-critical nature of the item, which limits competition to previously approved sources only. Interested vendors must submit detailed technical data and documentation as outlined in the NAVSUP Source Approval Information Brochures, as failure to do so will result in disqualification from the bidding process. Proposals must be submitted within 45 days of this notice, and all inquiries should be directed to Jacob A. Tarini at jacob.tarlini@navy.mil or by phone at (215) 697-3563.