Features:
- Works with LiftMaster® models 2500, 3500 and 3800 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 Battery Backup is charging, in use, or when the batteries need to be replaced.
