1Automatic Power Off: After continuous heating, this cup warmer will automatically power off, so you don't have to worry too much about forgetting to shut down. 255C Constant Temperature: Under working condition, hot water will be cooled to warm water and cold water will be heated on this electric cup warmer. Continuous constant temperature 55C without cooling. 3USB Power Supply: Electric coffee mug desk warmer adopts convenient USB port, can be powered by charging bank, computer and charging adapter. 4Anti Slip: Metal heating plate is in CD grain design, and the bottom adopts 4 foot anti slip mat, which is anti skid and shockproof. Humanized design, safe and stable. 5Applications: This fast heating cup warmer can use most flat bottom containers on it, such as ceramic cups, glasses, boxed milk and other flat bottom containers. Perfect for hot coffee, tea, hot cocoa, milk.