Crafted for the relentless adventurer, G-Tech&';s 4.0 battery ensures you&';re powered for any expedition. Providing 12+ hours of uninterrupted heat backed by cutting-edge technology, our batteries stand the test of time. Order a spare to double your usage and never be left in the cold again. 4.0 Battery Upgrades: USB-C charging compatibility for simple, universal charging Integrated LED battery-level display so you always know how much power you have left Extended runtime across all heat settings, giving you longer-lasting warmth Multi-use portable power bank functionality, allowing you to charge additional devices via USB or USB-C ports *The 4.0 Battery is compatible with 3.0 Heated Pouch Models* *Each 4.0 Battery also comes with a USB to USB-C cord*