The Department of Defense, specifically the Department of the Navy through NAVSUP Weapon Systems Support, is soliciting proposals for the procurement of heat exchangers as part of a sole source requirement. This procurement involves the purchase of spare parts that necessitate Government Source Approval prior to award, as the Government lacks sufficient data to contract with sources other than the current supplier. The items are critical for maintaining operational readiness and compliance with military standards, and interested vendors must submit the required documentation as outlined in the NAVSUP WSS Source Approval Brochure. For inquiries, potential bidders can contact Jessica P. Laychock at 215-697-3992 or via email at JESSICA.P.LAYCHOCK.CIV@US.NAVY.MIL.