Rechargeable lithium battery for Familock S3&S3 Max

This is the best lock ever. You can see who is at the door without trying to figure it out through a little hole

I purchased backup batteries, so the unit would always have a backup ready. The previous smart lock I had made by Yale had a lot of problems.. this is why I converted and came to this particular smart lock because of the rating now I’m finding that the battery back up system is 100 times better than anything on the market

Works Great

Works great! I keep coming back to eufy. Very happy with the products.

Fast deliver and good price

Good to have. Makes charging up a smooth transition.

I found the delivery on the front porch of my old house which we are selling. It was sent to the wrong address. It’s now a spare battery

charged the battery on low energy source . took almostv2cdays, but very timely. original battery exhausted it's charge and the replacement slipped right on. works great.

Very good

Received in excellent condition. Works as described andtwo batteries should be included with the purchase of an eufy smart lock.