Features [Good heat dissipation] This regulator has the characteristics of 0 lag, 0 delay and super high heat dissipation. [Multiple protection] This regulator is anti-surge, RC absorbs multiple protections [High practicality] Connect this device in series with light bulbs or household appliances, and then turn the knob for dimming, rate, voltage, and temperature control. [High-quality material] This regulator uses high-quality SCR, the maximum current is up to 25A. Solve the problem of overcurrent caused by too small wire resistance during cooling [Scope of application] This regulator is used to adjust the rate of the motor, and the output voltage can be adjusted by a precision multi-ring potentiometer. Features: This voltage regulator is used for motor rate regulation and can adjust the output voltage through the precision multi-ring potentiometer. Ac 0v-220v continuously adjustable, 0 lag, 0 delay, ultra-high heat dissipation. Anti - surge, anti - pea/k, RC absorption multiple protection. Connect this device with lamp or home appliance in a series connection, then rotate the knob for dimming, rate, voltage, temperature control. This controller is adopt of high-quality SCR, and the m/ax current is up to 25A. It solves the over- current problem caused by too little resistance of the wire during cooling Specification:  Voltage: AC 220V Maximum power:4000W Voltage regulation: AC 0-220v Circuit board: FR-4 circuit board M/ax. current:40A Size: 6*4*4.5cm/2.4*1.6*1.8in Weight: Approx.75g/2.6oz Note: load must be applied first to adjust voltage. Use method: The voltage regulator can be used in the circuit in series, and the voltage regulator can be connected to the lamp and electric appliance in series (that is, either the lamp or electric appliance can be disconnected from the fire line or 0 line, which can be connected to the terminal of the "product"). Simple and convenient operation. Note: you can't adjust voltage before connecting the load Package list:  1 x Motor Sp/eed Controller Package List