AGM Battery Standby Sump Pump Battery 12V 81.5 AH by Basement Watchdog

Maintenance free - no need to add battery fluid or distilled water

Runs sump pump intermittently for days

Compatible with BWE, DFK961, Basement Watchdog special, BWSP+, BWD12-120C+ and BW4000

Up to 80-hour protection (based on a 10% duty cycle) on the BWE and DFK961

Not compatible with older versions of BWSP, BWD12-120C or BW4000 systems