The Black Diamond Check Valve is a genuine replacement part designed to help maintain proper compressor operation by preventing air from flowing back from the tank into the compressor head. Featuring a 1/2 in. NPT x 3/8 in. tube connection with a 1/8 in. right angle bleeder, this durable valve closes securely once air has been drained from the compressor head. It includes precisely machined threads—1/2 14 NPTF on the 1/2 in. O.D., 9/16 24 UNE 2A on the 3/8 in. O.D., and 7/16 24 UN 2A on the 1/4 in. O.D.—and a 1/4 in. port that accepts aluminum, copper, or nylon tubing. Ideal for replacing a leaking or non closing valve, it helps restore reliable, efficient compressor performance.