... Details about product: 1. Materials: silicone rubber o-ring for toys, also can be NBR, EPDM, Viton, ... anti-toxic, good air-permeable silicone rubber o-ring for toys, etc.4. Hardness: 20-80 ... and no flash.7. Color: black silicone rubber o-ring for toys, transparent, green, red, yellow, grey, ... production cost optimization.Our advantages:1. All AS568, JS, BS, Metric standard sizes are in ready stock. ...