The Department of Defense, specifically the Department of the Navy through NAVSUP Weapon Systems Support, is seeking qualified sources for the procurement of 10 units of a Diplexer, identified by NSN 7R-5985-015342170-YW and part number MD-100K021. This presolicitation notice indicates that the items are critical components within the category of antennas, waveguides, and related equipment, which are essential for various defense applications. Interested parties are encouraged to express their interest and capability to fulfill this requirement, with proposals being accepted within 45 days of the notice publication, or 30 days if awarded under an existing Basic Ordering Agreement. For further inquiries, potential bidders can contact Brian J. Emde at (215) 697-4313 or via email at BRIAN.EMDE@NAVY.MIL.