... ring 1.water, oil resistance, anti-aging 2.silicone,rubber material 2.FDA,ROHS,SGS Certificate Factory history8 yearsFactory area3700m2CertificateSGS, ROHSMachines(20sets)Rubber ... ),NR,PU etc.Material PerformanceRebound resistance, Tear Resistance, Abrasion Resistance, Impact Strength Resistance, Gas Impermeability Resistance, Oxygen Resistance, Flame Resistance,Heat ...