Ensemble de batterie de secours pour douche numérique Smart Shower avec 6 piles D 179573

Is a simple battery back up. Nice that it came with batteries

Allows you to finish a shower during a power outage. The batteries last over a year.

Not sure my system really needs this unless the power is out for an extended period of time. Not sure why it uses D cells, but at least Moen includes them.

Works well. The batteries last a surprisingly long time…about 18 months. Just make sure you have an access door large enough to get the battery pack, water valves, electrical outlet, and Moen U controller. A 2x4 stud is s wide enough to mount.