... to design and manufacture small-scale combination valve, automatic compensation for plunger shut-off valve, self sealing valve and double-headed ... of technical supervision and certification of ISO9001 quality system.Parameters Pressure level,PN64Nominal diameter,DN20Seal property,gas leakage≤1×10-15 ... ),O-ring,Plastic protection caps,Meter connector,Inflatable valve high pressure Self-sealing valve