Mr Beams MB220 ReadyBright Wireless Power Outage LED Lighting System - Smart Power Outage Detector (Includes 1 detector only) Plugs into a wall outlet and detects a power outage transmits an RF signal to wireless lights to automatically turn them on when the power goes out Can be unplugged and used as a powerful flashlight that can be used anytime Acts as an easy remote control that turns all system lights on and off to conserve battery life Sends an instant signal to lights up to 70 feet away and can span more than a 2,500 square foot house Great solution to provide lighting for safety and secuity for residential power outages