1、With a peak voltage absorption circuit, it effectively protects the high‑power SCR anti‑surge, anti‑spike, RC absorption multiple protection. 2、Original imported chip SCR, all‑aluminum heat sink, high‑temperature circuit board. 3、Built‑in accurate resistance, high voltage capacitor, stable output, no lag and delay. 4、Use multifunctional industrial sockets, thick copper parts, thicker parts inside the copper parts, high current, good contact and safety. 5、The metal casing has the characteristics of high temperature flame retardant, no deformation and no rust, which can effectively prevent high temperature, heavy pressure. 6、With stepless variable speed adjustment, free control adjustment, no gear limit. Material: Cold rolled steel, aluminum alloy, thyristor, PCB Item Parameter Output voltage 0-220V adjustable (Voltmeter does not work when the output voltage is lower than 5V) Limit power 4000W (adapt to 2000W-3000W resistive load) Regulating range 0-220V steplessly adjustable (under load condition) step-down to 0V, step-up 10V Rated current 9A Limit current 18A Overload protection switch Yes Thyristor model STMicroelectronics, Thyristor: BTA41-600B/800B Size: Approx. 5.3cm / 2.1in 10cm / 3.9in 8.4cm / 3.3in Precautions and Instructions for Use: 3. The 4000W mentioned above refers to the limit power when working in a resistive load. The inductive load is 1/3 of the resistive load. The resistive load refers to the tungsten filament lamp, heating wire, etc., and the inductive load refers to the series motor. And so on, there are circuit board electronic products used with caution. 4. The metal shell of this product must be safely grounded 1 x AC Voltage Regulator