XIANQI Specification:Size: approx. 85*58*38mmWorking voltage: AC 220VMaximum power: 4000W (connected resistive load)Voltage regulation:AC 0-220V, start from AC 10VProtection: anti-spike, Surge, RC absorption (EOC)Stable and durable.Used in electric furnace, water heater, lamps, small motor, electric iron etc.How to Use:The input is connected with the AC 220V.Output wire is connected to the electric stove wire or motor appliances.Then rotate the knob for speed, voltage, temperature controlPackage included:1pc x Voltage RegulatorNote:Load does not exceed the maximum power, otherwise it will burn module and electrical appliances; use the resistive load as far as possible; reduce inductive and capacitive load power greatly. ( it is best to leave more than half of them).Please allow 1-5mm errors due to manual measurement.Item color displayed in photos may be showing slightly different on your computer monitor since monitors are not calibrated same.