ヒートソックス用追加バッテリー

I've been wearing these for full work shifts in a cold warehouse, and the battery easily lasts through my entire 10-hour day without needing a recharge. It charges up in about an hour, which is convenient for quick turnarounds between shifts. A solid spare to have on hand.

My old battery drained before the end of a long ski day, but this spare swaps in seamlessly and keeps the heat going for hours—exact fit, no fiddly connectors. Wish it came with a charging cable, but the battery itself works flawlessly.

Was tired of my socks dying halfway through a long hike, so this extra battery solved that perfectly. It clicks in securely and lasts just as long as the original, about 5 hours on medium heat. Exactly what I needed for all-day warmth.