1. Constant Temperature: Coffee mug warmer is a 55C smart constant temperature coaster that keeps the temperature at all times.2. Space Saving: Candle warmer plate only needs palm sized space, small in size, and does not occupy the desktop, keeping the space tidy at all times.3. Small Portable: The USB candle warmer is compact and lightweight, making it a must have for home, office, and outing.4. Automatic Function: Candle warmer automatically heats the water cup, automatic power off, safer to use.5. Tempered Glass: Mug warmer's panels are made of tempered glass, which is waterproof, strong, wear resistant, and .Spec:Item Type: Coffee Mug WarmerMaterial: Aluminum Alloy,Tempered GlassInput Voltage: 5V/2AOutput Power: 8 to 10WTouch Function: High Grade, Mid Grade, Low Grade, OffRed Light High Temperature File About: 55 to 60?Blue Light Medium Temperature File About: 50 to 55?Green Light Low Temperature File About: 40 to 50?How to Use:Plug and play, the indicator light is on when heating works.packing list:1 x Coffee Mug WarmerNote:1. The actual temperature is affected by the thermal conductivity of the cup and the conditions of use.2. Automatic power off after 8 hours of work.