This is the XS Scuba Thermo Diving Tank Valve Deluxe K 3000 PSI Air Features: Standard yoke outlet 3/4"-14 NPSM standard inlet threads Air service only Quality, dependability and reputation have made this valve the most popular, widely-used valve for scuba cylinders in the world. The Thermo K valve is used by more dealers, resorts and boat operators than any other valve. Trust the valve the professionals use.