eufy Rechargeable Battery for eufyCam S4, S330 3-in-1 Video Smart Lock, E330 Video Smart Lock, Smart Lock S230, Smart Lock E31 and Smart Drop, Black

The 10,000 mAh capacity lasts way longer than the single-use ones I was burning through every few months. Swapping it out without unscrewing the lock from the door is a small thing but honestly makes a big difference.

Having a spare battery means my doorbell camera never goes dark while the other one charges. The 10,000 mAh cell easily gets me through a couple of weeks, which beats buying disposables every time.

Swapping this in took about ten seconds and I didn't have to unmount the doorbell at all. Nice not buying disposables every few months, and it charges fast enough that I barely notice it's gone.