The S-Pack 700 battery has a maximum autonomy of 8 hours. It has three different intensity levels, allowing the user to adjust the level of heat to suit their needs. It can be recharged using the included USB charger. The pack includes two rechargeable batteries. Easily adaptable to compatible heated socks to provide constant heating during winter outdoor activities. In a nutshell Pack of two S-Pack 700 batteries Heating time level 1: up to 8 hours Heating time level 2: up to 5 hours Heating time level 3: up to 2 hours S-Pack batteries are compatible with Therm-ic Powersocks Pack includes a USB charger to charge both batteries simultaneously List of compatible heated socks The S-Pack 700 battery is designed to be used with our Therm-ic heated ski and outdoor socks. Here is the list (from the oldest to the newest): Heated ski socks : Powersocks Heat Men ND Powersocks Heat Women ND Powersocks Heat Uni ND Powersocks Heat Fusion Uni Powersocks Heat Fusion Men Powersocks Heat Fusion Women Powersocks Heat Fusion Uni ND Ultra Warm Comfort S.E.T®* Ultra Warm Performance S.E.T®* *If you're looking for batteries for the Ultra Warm S.E.T® heating socks, we recommend the S-Pack 1400B batteries. Outdoor Heated Socks : Powersocks Heat Multi Powersocks Heat Multi ND Powersocks Heat Fusion Outdoor
