... :NBR/VITON/SI/EPDM 3.SIZE:standard and non standatd V RINGWHY CHOOSE US?1. ROHS and REACHapproved.2. Reasonable and ... , valve rubber products, o ring kit, o ring, x ring, v ring, oil seal, wiper seal, u ring, rod seal, piston ... .The formulation of partial products is independent research and development by us. V RING(VA/VE/VL/VS) Hydraulic seal(Ozone resistance)