... , wax melting heater,vapor generator,humidifier,water boiler,liquid warmer,coffee warmer,polymer press-coating heater,hot glue gun,chocolate extruder ... ,shoe dryer,hand/foot warmer,massager,physical therapy heater.Notice in appliance. 1) ... voltage increases (or decreases) 2 time. In liquid heating appliance, when liquid was dried in the container, its no problem ...