This is a kind of fine quality high power SCR voltage regulator, stepless regulation, help adjust speed, temperature, voltage and light. Adopt high-temperature resistant FR-4 circuit board, origin imported chip SCR, full aluminum thermal fin, precisions resistance with high voltage condenser. No postpone and no delay, with crest voltage absorb circuit, can protect the high power SCR effectively. You can have a try. Features: Mini size, portable and lightweight, strong power, easy to use. High power SCR voltage regulator, stepless regulation, help adjust speed, temperature, voltage and light. Adopt high-temperature resistant FR-4 circuit board, origin imported chip SCR, full aluminum thermal fin, precisions resistance with high voltage condenser. No postpone and no delay, with crest voltage absorb circuit, can protect the high power SCR effectively. Anti surge, anti-spike, RC absorb and multiple protection. Flame retardant insulation outshell, high temperature resistant, rustproof, anti high pressure and with fine durability. Adopt multi functional industrial sockets, thicken copper part design, with fine contact and safety. Humanized installation hole design, keep flat place or hanging on it is decided by yourself. Silent work, energy saving, stable anti-noise, and with wide range of use. Suitable for water heater, tungsten lamp, small motor, electric iron and etc.. Notes: When measuring the output voltage when it is empty, it is a virtual voltage. It must be connected to a load of 20W or more to measure the correct output voltage. Input AC power, the output is also AC, not DC. The above mentioned 4000W refers to the ulti mate power when working under resistive load. The inductive load is 1/3 of the resistive load. The resistive load means that the inductive load such as a tungsten filament lamp or a heating wire is a series-excited motor, etc., and the circuit board electronic products are used with caution. This product is a metal case and must be grounded safely. Specifications: Name: SCR Voltage Regulator Material: aluminum Color: grey Input voltage: AC 220 V Output voltage: 0-220 V Max power: 4000W Voltage adjusting range: 0-220 V Rated current: 9A Max current: 18A Main machine size: 100 * 83 * 75mm / 3.94 * 3.27 * 2.95in Item weight: 418g / 0.92lb Package size: 145 * 85 * 105mm / 5.71 * 3.35 * 4.13in Package weight: 450g / 0.99lb Package list: 1 * SCR Voltage Regulator