Features: 1) This device can be widely applied in household, department, school, hotel, restaurant, shop, net bar, beauty shop, small factory. Its life span can be six to eight years 2) Usage: this device can be installed freely 3) Work load: 1,500W-2,000W, this device consumes 1W electricity itself 4) Life span: six to eight years 5) Remark: the effect is distinct after a month, the longer time you use it, the more electricity you will save. Consider installing several devices if the load is heavy