This coffee warmer not only can slow down the cooling speed of hot beverage, but also can heating cold beverage.You can concentrate on what you are doing. A drinkable beverages always ready for you Safe & Reliable cup warmer is versatile. It can heat coffee, milk , water etc. It does not support to boil liquids.this temperature we design according to the health needs of the human body. So don't expect it to heat your drink very hot like a microwave or a kettle.