Extra battery is perfect. 3 weeks ago we killed 2 bulls...cut all night and had our "other" headlamps on...well, they all died before first light on our packout. I called my wife and asked her to order a Peax headlamp...got it and just came back from a 4 day hunt and never even needed the spare battery...great product and if the main battery dies, I have a spare now. Good stuff!
Eric

I bought it as a spare. The battery life is incredible!!

Backup battery is great to have on hand for overnight lighting. Exactly what I needed to make sure I’m ready for adventure.

Now I have a spare if needed

Head lamp / batteries (the one that came with the headlamp and the extra battery that I purchased) stopped charging. I asked for replacement batteries per the warranty, but they wanted everything returned so they could check the head lamp to make sure that wasn't the problem. I returned everything to the company for them to look at...they replaced the headlamp along with both batteries. This type of service and commitment to a company's product is almost nonexistent anymore. Excellent job!