O ring specifications are mainly UHSO ring specifications, UHPO ring specifications, UNO ring specifications, DHO ring specifications, piston rod O ring specifications, high temperature resistance O ring, high pressure O ring, corrosion resistance O ring, wear resistance O ring. O-ring standards are GB 1235-76, GB GB34552.1-92; Daily standard P TYPE, G TYPE, S TYPE, SS/V TYPE, F TYPE; American Standard AS568, British standard series; European standard series O-ring technical requirement