... resistant, good insulation property, anti-toxic, good air-permeable silicone rubber o-ring for toys, etc.4. Hardness: 20-80 ... strictly upon international standard, and no flash.7. Color: black silicone rubber o-ring for toys, transparent, green, red, yellow, grey, ... : poly bags inside, strong carton and PE film paper packed outside, can be water proof.product pictures: Anti-toxic silicone rubber o ...