STAY CHARGED ALL DAY! Maintain warmth and comfort with our portable batteries & chargers to keep your heated clothing powered up and ready to go. Fieldsheer’s portable batteries and chargers allow you to stay in the field longer, travel further, and get the job done. Our complete line of chargers and batteries is compatible with cars, wall outlets, USB comes in a full range of voltages. Designed for portability and access, you can rest easy with Fieldsheer’s batteries and chargers in hand.