O-ring Main type: VITON o-ring, Silicone o-ring, Nitrile o-ring, EPDM o-ring, HNBR o-ring, CR o-ring, BUNA o-ring. O-ring Characteristic: Bears the high temperature, has extremely good bears the climate, bears the ozone and bears the chemical properties, bears the petroleum. O-ring authentication: USA NSF/FDA; German DVG/KTW; UK WRAS. O-ring uses in astronautics, the automobile, the medical service, the drugs manufacture, the satellite, the valve, pump, the bathroom, the electron, the electric appliance, and so on industry. The precise O ring surface is smooth, none the needle eye, none the fragments, the precision achieves +/-0.03 mm to +/-0.08 mm. O-ring series: AS 568 O-ring, JIS PG O-ring, GB O-ring.