The Petzl Core Battery serves as a reliable power source for your Petzl Headlamp (consult tech specs for model compatibility) when you're alpine climbing, backcountry skiing, or backpacking after dark. It's rechargeable via USB for convenience, complete with an indicator light for an accurate read-out of its charging status and remaining burn time. Pick one up as a replacement for your older battery or grab a second battery as a reliable back-up when you're miles from the nearest sign of civilization.