This controller uses novel bi-directional high-power SCR. It can be very convenient adjust the current up to 25A, and solve the over current problem of the heating wire resistance is too small in the case of cooling causing good. The output voltage is adjusted anywhere between 50V-220V for use with electrical appliances. It can use to such as electric stove, water heater tune thermal, lighting dimmer, small motor speed, electric iron thermostat, and achieve dimming, thermostats, pressure regulator effect. Specification: -Input supply voltage: 110V ~ 250V AC -The output voltage:50V-250V (Output voltage <= Input supply voltage) -The maximum output power: 2000W -The maximum output current :25A -The voltage regulating range:50V-250V AC (Output voltage <= Input supply voltage) -The operation environment temperature:-20C-40C -Size: Approx. 47*35*27mm Package Included: 1 pcs x 50-220V 25A AC Motor Speed Controller Note: 1.Please allow 0.1-0.3cm differences due to manual measurement, thanks. 2.Please understand because of the light irradiation or computer display difference, so I can't guarantee photos and real color is 100% the same.