The use of a new type of high-power bidirectional thyristor is a good solution to the overcurrent problem caused by electric furnace wire when the resistance is too low during cooling, because the design current can reach up to 20A. It is very convenient to adjust the output voltage of the power supply and can be set anywhere in the range from 0 to 220 volts for electrical appliances. Rotate the potentiometer lever to adjust speed, voltage and temperature. Such as: electric cooker, boiler heating adjustment, lamp light adjustment, motor speed adjustment, electric soldering iron temperature control, etc. For dimming, temperature and pressure effects. Please note that the load must not exceed a certain maximum power, otherwise the modules and electrical equipment will burn. Can be used for large electrical appliances with a power consumption of less than 4000 watts. Since the power is already high, general household electrical appliances or small factories are enough. Specification : Use voltage: AC 110 V-220 V High power: 4000W (connected to resistive load) Voltage regulation: adjustable in the input voltage range AC 0-220V Size specification: 91*59mm (without handle) 34mm (total height) Package includes: 1x regulator