JSS Set of 2 Round Silicone Mug Coffee Cup Cap, Seal Air Tight Drink Cup Lid, Tea Glass Cup Cover, Spill Proof Suction Lid Tumblers (Grey) Diameter: 4.25Inch/10.8cm Material:100% Food-Grade silicone, FDA approved Heat-resistant ( from -40 to 446 F), non-stick, non-toxi, odourless and non-hazardous, Microwave safe. Easy to Clean, can be washed in the dishwasher. If you like silicone products, please visit our store.