This is a high-quality high-power thyristor voltage regulator with stepless voltage regulation, which can help adjust speed, temperature, voltage and brightness. It adopts high-temperature resistant FR-4 circuit board, original imported chip thyristor, all-aluminum heat sink, precision resistor with high-voltage capacitor. Independent switch control, you can freely control the input power and cut off the power. No delay, no time delay, with peak voltage absorption circuit, can effectively protect the high-power thyristor. You can try it. Features: small size, portable and light, strong power, easy to use. High-power thyristor voltage regulator, stepless regulation, helps to adjust speed, temperature, voltage and light. It adopts high-temperature resistant FR-4 circuit board, original imported chip thyristor, all-aluminum heat sink, precision resistor with high-voltage capacitor. Independent switch control, you can freely control the input power and cut off the power. No delay, no time delay, with peak voltage absorption circuit, can effectively protect the high-power thyristor. Multiple protections such as anti-surge, anti-spike, RC absorption. Flame-retardant insulation shell, high temperature resistance, rust resistance, high voltage resistance and good durability. It adopts multifunctional industrial socket, thickened copper design, good contact, safe and reliable. Humanized mounting hole design, you can decide whether to lay it flat or hang it. It works quietly, is energy-saving, stable and noise-resistant, and has a wide range of uses. It is suitable for electrical components, such as: electric furnaces, water heaters, thermal conduction lamp dimming, small motors, welding thermometers, etc. Note: The output voltage measured when no-load is a virtual voltage, and a load of more than 20W must be connected to measure the correct output voltage. Input AC, the output is also AC, not DC. The 4000W mentioned above refers to the limit power when working on a resistive load, and the inductive load is 1/3 of the resistive load. Resistive load refers to inductive loads such as tungsten filament lamps, heating wires, series-excited motors, etc., and circuit board electronic products should be used with caution. This product has a metal casing and must be safely grounded. Specifications: Name: SCR voltage regulator Model: NHT-4000W Material: Aluminum Color: Black Input voltage: AC 220 V Output voltage: 0-220 V Maximum power: 4000W Voltage adjustment range: 0-220 V Rated current: 9A Maximum current: 18A Host size: 115 * 100 * 83mm / 4.53 * 3.94 * 3.27in Product weight: 459g / 1.01lb Packing size: 180 * 100 * 115mm / 7.09 * 3.94 * 4.53in Packing weight: 522g / 1.15lb Packing list: 1 * SCR voltage regulator"