Chamberlain CG40D 1/2-HP Chain Drive Garage Access System Quick-install rail system provides faster and easier installation - assembles in 60 seconds Protector system safety sensors with Rapid-Snap brackets PosiLock theft protection assures that once the door is closed, it says locked Security plus anti-burglary technology assures a new code is sent every time the remote control is used Includes one single-button remote control and an illuminated door control button