Zodiac Coffee mug set with the coffee warmer

The Coffee mug set with the coffee warmer has a constant temperature no more cold coffee. The temperature of your coffee just steady as long as you want Modem Coffee mug warmer with heater has constant temperature thermal 55-degree coffee mug set 1. 55 centigrade constant temperature 2. Normal power charger (USA Canada Cable Plug) I have tested all the coffee warmer to make sure all works properly. (Quality control)