... . 4.ROHS approved. Details about o ring color code: Materials Comply with ROHS, NBR, Silicone (VMQ), EPDM, Viton, etc.Characteristics Good physical ... as your request.Tolerance Strictly upon international standard, no flash.Color Black, transparent, green, red, yellow, grey, purple, pink or as ... , Metric and BS o rings are all available. o ring color code