What it can do-- With a countdown function, you can set a certain time to turn off devices, improve your home security and make your life easier and safer Prevent overchargingWhen the battery is fully charged, it will automatically disconnect the circuit, effectively preventing electronic equipment from being overcharged. Ideal for home lighting, fans, air conditioners, humidifiers, Christmas trees and more Wide Application-- The timer power outlet switch is widely used at home. home, hospital, school, etc. Saves energy and costs, reduces the risk of fire and prolongs the life of the device Multi-function--This product is a countdown timer, measuring the consumption of energy, voltage, current and time of electrical devices at the same time, such as a multi-function socket