Adjustable voltage range: The adjustable voltage range can be really smooth and adjustable from 10V to 220V, which makes it more suitable for devices that require low voltage to drive the heating wire Dual capacity design: 220V voltage regulator adopts amperometric capacity + a metal film ability to absorb voltage surges and spikes, more efficient and safer to use Wide Application: Use to adjust the speed, brightness, voltage, temperature of various electronic devices, such as electric oven, water heater, lamps, small motor, etc. Why choose our AC voltage controller? Design capacity Dual: Adopt amperometric capacitance + metal film capacitance to absorb surge and voltage spike, more efficient and safer to use.Durable performance: Using high quality housing, which is made of 1 aluminum .5mm thickness and stainless steel, safe and convenient. Easy to use: Easily control voltage, speed, temperature and more via the adjustable rotary knob. Specifications: Color : silver Material: aluminum + stainless steel Input voltage: AC 220V Voltage Regulation: AC 10-220V Power: Max. 4000W Efficiency:andgt; 90%Size: approx. 85 x 55 x 38mm3.3 x 2.2 x 1.5inch Package Weight: 127g Package List: 1 x Voltage Regulator Note: The charged power cannot exceed the specified maximum power, otherwise it will burn the module and the electrical appliance.