The Department of Defense, specifically the Department of the Navy through NAVSUP Weapon Systems Support MECH, is seeking to procure four units of the left heat exchanger (NSN 0O-1660-016836911) under a presolicitation notice. The procurement is set aside for small businesses, as indicated by the Total Small Business Set-Aside designation, and the items are classified under the PSC code 1660, which pertains to aircraft air conditioning, heating, and pressurizing equipment. This equipment is critical for maintaining operational efficiency in military aircraft systems. Interested vendors should direct inquiries to Sarah Haley at (717) 605-3550 or via email at SARAH.R.HALEY2.CIV@US.NAVY.MIL, and must respond within 15 days of this notice to express their interest and capability to meet the requirements.