Liftmaster 475LM Evercharge Battery Backup System

Liftmaster EverCharge Garage Door Opener Battery Backup System 475LM Works with LiftMaster models 2500, 3500, 3800 and 8500 garage door openers; Operates the garage door opener as if the power was still on (all safety and security features still operate); Audible signal sounds when door is moving under battery power; Bright LED lights let you know when the EverCharge is charging, in use, or when the batteries need to be replaced. The 475LM Battery Backup System is always charged and ready, the EverCharge powers LiftMaster models 2500, 3500, 3800 and 8500 garage door openers to open and close the garage door up to 20 full cycles when the power goes out. All safety and security features still operate while in use.Liftmaster 475LM is simple to install, it sits on top and plugs right into the back of the garage door opener. For low headroom installations, the EverCharge‚ can also be mounted to a joist/rafter on the ceiling.A large number of homes are already adding this type of power backu