Material :Rubber+Carbon Fiber Size:appr 9.5��0.6cmColors:Red， Green， Blue.if not note will random.Package:1x coffe cup warmer heater.USB powered �C Plug & Play! Keeps drinks warm at 50 degrees C Works with all Mac and PC USB Ports DO NOT USE plastic or foam cups WARNING �C surface can get very hotNote:Suit for Flat container above 75 degrees of heat-resistant materials， etc.