Rubber seals, polyurethane seals, plastic sealsO-ring: a national standard, American standard, Japanese standard, materials are fluorine rubber, nitrile rubber, silicone, chloroprene rubber, hydrogenated nitrile rubber, polyurethane and so on.Y-ring: UN, UNP, UHP, U32I, SODI, IDI, YXD, YA, KYD.Dust ring: DHL, ADA, P6, FJ, FA, etc.Combined..