... .The diameter:120.00mm 2.Good quality and Best Service 3.Oem is welcome our company is a leading piston ring ... in China, founded in 1986, can make high-quality piston ring to meet market's need with bottom price, ... SprayingGas NitridingMoS2 CoatingPTFE CoatingCopper PlatingTin PlatingPhosphatingOxidingCeramics penetrating4,annual turnout : piston ring: 60,000,000pcs valve seat inset:10,000, ...