... competitive price. 4.ROHS approved. Details about o ring color code: Materials Comply with ROHS, NBR, Silicone (VMQ), EPDM, Viton, etc ... and PE film paper packed outside with water proof. Capability of our workshop: 1. ISO9001:2008 certificated factory.2. Mix materials ... new projects with high efficiency.We have thousands of current molds for all kinds of o ring, AS568, JS, Metric and BS ...