IST Scuba Air Tank/Cylinder Valve Knob Green

The IST SCUBA Air Tank / Cylinder Valve Knob is a durable valve knob for air cylinders, available in black to signify an oxygen air mix or green for Nitrox cylinders. Constructed of sturdy hardened rubber with metal plate insert, the knob features an outer surface that s ribbed for easy grip. Measuring 1.75 inches in length, the knob has an exterior diameter of 1.5 inches. The words OPEN and CLOSE with accompanying directional arrows are molded into the end of the knob, to help prevent over-tightening.