The Department of Defense, specifically the Department of the Navy through NAVSUP Weapon Systems Support, is seeking proposals for the procurement of six units of a flight-critical filter assembly, identified by NSN 7R-1660-017003352-P8 and reference number 2170119-101. This procurement requires government source approval prior to contract award, as the item is essential for aircraft air conditioning, heating, and pressurizing equipment, and only previously approved sources will be solicited. Interested parties must submit their proposals along with the necessary source approval documentation within 45 days of this presolicitation notice, with all inquiries directed to Jacob A. Tarini at jacob.tarlini@navy.mil or by phone at (215) 697-3563.