Pneuflex's SPOC 14-03 model is 14mm O.D tubing x R, PT, BSPT 3/8 thread stainless steel hex socket head male connector push in air fittings, of which body is round. Connect pneumatic tube of 14mm diameter and installed to the R 3/8 female thread. Its internal hexagon allows tightening with a hexagon wrench in confined spaced. 14mm x R 3/8 stainless steel round male straight pneumatic air fittings are made entirely of high grade stainless steel material, suitable for use with both hard/ soft tubing made of nylon, polyurethane, polyethylene, Teflon, allowing steam, oil, water and other corrosive liquids flowing through.