MD Sports DB800Y19007 is a laser toe line device designed for indoor use. It projects a laser line on the floor to help you line up your darts throw. The device is powered by 4 "AAA" batteries (not included) or an optional power adapter (not included). It features two white lights and an infrared light, and can be operated using the "ON/OFF" key. The mounting bracket allows you to hang the device on a cabinet or wall, and the adjustable housing ensures proper positioning of the laser line. The device includes a battery box for easy battery installation and replacement.