AUTOTOOLHOME Adjustable AC 50-220V MAX 2000W SCR Voltage Regulator Speed Controller Dimming Dimmers Thermostat Control Module Protection Switch Able to easily adjust the electricity the output voltage between 0-220 volts, Use with electrical appliances. Such as: furnace, hot water heater tune, lamp dimmer, small motor, electric iron thermostat and so on. So as to achieve dimming, thermostats, pressure effect. Available for less than 2000W of electric power large appliances used because the power has been great, the general home appliances or small factories sufficient.