... :NBR/VITON/SI/EPDM 3.SIZE:standard and non standatd O RING WHY CHOOSE US?1. Certification: ISO9001, ROHS, REACH, ... to meet FDA, RoHS, SGS, UL, NSF, WRAS, etc.Our rubber products include: bearing seal, valve rubber products, o ring kit, o ring, x ring, v ring ... , oil seal, wiper seal, u ring, rod seal, piston seal, rubber ...