SPOC 5/16-01 is a model number of 5/16" O.D tubing x R 1/8 male thread hex socket head male connector stainless steel push in air fittings. Its round shaped body and internal hexagon helps it to be installed anywhere space is limited, tightening with a hexagon wrench. Connect 5/16" pneumatic tubing and installed to R, PT, BSPT 1/8 female thread. 5/16" x R 1/8 stainless steel round male straight push to connect air fittings are made to be non corrosive and highly resistant to aggressive environment, as well as corrosive fluids.