Ergodyne - EGO41801 N-Ferno 6495B Portable Battery Power Bank is a compact, lightweight, lithium-ion battery designed to charge the N-Ferno 6495 Rechargeable Heated Vest (not included). High-capacity, 7.2-volt battery with 5000mAh charges quickly and offers all-day use when fully charged. Battery pack takes up to 4 hours to fully charge. It is recommended to use a 2 amp charging block (not included) with the included charging cable for easy recharging. Colored, LED light gauge on the battery pack indicates battery life. Fully charge the battery every 6 months if it's not used on a regular basis.