silicon ring Made of 100% silicone ,come up with RoHS standard, soft in texture ,good feel and tear-proof. Silicon ring 1. Made of 100% silicone ,come up with RoHS standard, soft in texture ,good feel and tear-proof.2. Non-toxic,tasteless,non-corrosive, natural sound and environmental. 3. Any shape/color is available. 4. OEM /ODM is welcome.