The N-Ferno 6495B Portable Battery Power Bank (7.2v/5000mAh) is a compact and lightweight lithium-ion battery designed to charge the N-Ferno 6495 Rechargeable Heated Vest. Featuring a high capacity 7.2 V/5,000 mAh battery, this battery pack charges quickly and offers all-day use when fully charged (it takes approximately four hours to become fully charged). A colored LED light gauge on the battery pack indicates battery life, while the included USB-C cable makes for easy recharging. It is recommended that the battery is fully charged every six months, if not used on a regular basis. Battery Type: Lithium Ion; Battery Size: 7.2 V; For Use With: Ergodyne N-Ferno 6495 Jacket; Battery Capacity: 5,000 mAh.