Maintenance free - no need to add battery fluid or distilled water
Up to 40-hour protection (based on a 10% duty cycle) on Big Dog (BWD12-120C+)
Up to 48-hour protection (based on a 10% duty cycle) on Special + (BWSP+) and Basement Watchdog Big Combination sump pump system (BW4000, CITS-50)
Up to 80-hour protection (based on a 10% duty cycle) on Emergency (BWE) and Basement Watchdog Combination sump pump system (DFK961, CITE-33)
Runs various Basement Watchdog sump pump systems intermittently for days
Older versions, purchased before 2014 of Special, Basement Watchdog Big Dog and Basement Watchdog Big Combo systems that include the Remote Terminal are compatible with Maintenance Free/AGM Battery. Using a maintenance free battery with an older non-compatible system may cause false alarms.