VQF - T1 gas cylinder valves, suitable for filling in natural gas, gas or close of special equipment. The nominal pressure, nominal diameter 20MPa: 4mm; Applicable medium: Gas. And the cylinder threads for PZ/outlet connections to 27.8, threaded NPT1/4, board tight torque 22 ~ 26N. M, and shall be connected to cylinder seal belt wrapped, ensure good connections. Handle counterclockwise rotation 90 degrees for open. Strictly with wrench, beating handle switch. This product GB17926-1999 "according to the standard of compressed natural gas cylinder valves for manufacturing and acceptance.