Description:Thisis a easy-to use voltage regulator for controlling light brightness, speed or temperature. The big power voltage regulator is equipped with two-way silicon controlled rectifier, which is very convenient and practical. The voltage regulator has a large power and can be used for large household or small industrial electrical appliances of which power is less than 4000W(for resistive loads only, power should be reduced for inductive or capacitive loads). Features:This item has two-way large power silicon controlled rectifier and the current can be up to 20A, which is a good solution to over current of electric stove wire caused by low resistance during cooling. Convenient to use, simply connect input terminals to either live wire or neutral wire(220V) and output to load, then rotate knob to control voltage.With a wide voltage regulating range, the output voltage can be easily adjustedbetween AC 0-220V input voltageCould be widely used as heat controller on electric stoves, water heaters, light dimmer on lamps, speed controller on small motors, or temperature controller on electric soldering iron, etc. The resistive load power should be less than 4000W, and power should be largely reduced(half or more) for inductive or capacitive loads, otherwise controller and load will burn out.Specifications:Input Voltage: AC220VMax Power: 4000W(resistive load)Output Voltage: Adjustable between AC 0-220V input voltageSize: 85 x 60 x 45mm / 3.34 x 2.36 x 1.77" Package Includes:1 x Voltage Regulator Note: The maximum output voltage is equal to input voltage, e.g. if input 110V AC, the maximum output voltage is 110V AC; if input 220V AC, the maximum output voltage is 220V AC..