The brunton heavy metal 5500 power pack is the must have accessory for when you are out and about be it if you are out on the weekend adventure or a day time trip this power pack will save your electronics from running out of juice when you need them most thanks to its high grade lithium polymer 5500 battery that will charge faster and last even longer this brilliant brunton accessory has a built in usb to easily charge from any usb outlet and the charge time ranges between 6 8 hours the hea