Chamberlain 4228 Garage Door Opener Battery Backup provides reliable storm-proof power, ensuring your garage door remains operational even during a power outage. This non-spillable lead-acid battery is designed for fast and easy setup, allowing for up to 20 open/close cycles or 24 hours of operation when the main power is out. Compatible with all Chamberlain, LiftMaster, and Craftsman garage door openers that feature a Battery Backup System. The item is new in the original box, though the packaging shows some shelf wear and has been reinforced with clear tape.