Useful Area:1 Refrigerator, TV, Computer, microwave oven, electromagnetism oven, washing machine, heater, lamp etc.2 Results: For whole home appliance is about 15%-40%; For single device, light tube that is 19%,electromagnetism oven 13%, bulb 15% etc.Parameter:1 Rated Voltage: 200-240V 2 Rated Currency: 0-40A 3 Max Power :7000W4 Frequency:50-60Hz5 Single Phase