Note: Please allow 1-3mm differs due to manual measurement. Due to the different display and different light, the picture may not reflect the actual color of the item. Thanks for your understanding. Specifications: Resistance materials: metal and plastic Input voltage:AC 220V Voltage regulation: AC 50-220V Maximum power: 2000 W Dimension:48 x 56x 28 mm Connect this device with lamp or home appliance in a series connection, then rotate the knob for dimming, speed, voltage, temperature control. As the power has very big,so the normal home appliances or small factories enough to use. This pressure regulator with two-way high power silicon controlled, potentiometer have nuts, can use not need add any components, very convenient and practical Applicable Appliance: Electric furnace, water heater, lamps, small motor, electric iron. etc