Key Finder, GoerTek Wireless Intelligent key tracker/Lost Item Locator Remote Control with LED Lighting Function to find keys and small things lost easily 5 Colored Receivers Included Range 32 to 98ft Working Range: 10-30m; 1 Transmitter and Five Colored Receivers or lot applications both at home and office. The LED Flashlight on Transmitter Left Side to Help Light in the Dark; the Loud Beeping Sound (medium volume but not loud) will lead you to find the lost items quickly. Simple Matching and Convenient Searching -- Wireless Search that easily penetrates though walls, cushions and doors with a push of a button. GoerTek Wireless Key Finder can find some items like keys,mobile devices, small case, wallets, TV remote controller, hats, glass, umbrella, pets and more devices. Transmitter requires one 12V 27A Battery (included) and Receivers require CR2032 (3V) batteries (included)