This product is made from 100% imported pure silica gel raw materials, 100% food grade silica gel, detected by FDA material. The temperature resistance of silica gel products is - 60 ℃ - 250 ℃. High and low-temperature resistance, wear resistance, environmental protection, innocuity, dust resistance, durability, impermeability, and easy cleaning. Natural harmless, non-toxic, tasteless, non corrosive, environmental protection. 1 Pair in package