"RapidAir 1/2in. union elbow fitting along with other RapidAir components, sold separately enables you to expand your 1/2in. compressed air piping system, putting air lines exactly where you want them. Simply push air compressor tubing into the fitting until seated. Tubing can be removed by pushing on release button. Molded mounting hole makes for clean installation appearance. Coupler Size in. 1/2, Max. PSI 150, Pieces qty. 1."