Color Black Brand UltraFire Model 4 x 18650 Quantity 1 Piece Material Lithium ion Cell Type Lithium Ion Battery Model Others4 x 18650 battery pack Head Type Flat Top Mark Capacity 4400 mAh Actual Capacity 4400 mAh Voltage 7.2-8.4 V Rechargeable Yes Rechargeable Times Others500 Built-in Protected Circuit Yes Over Voltage Protection Yes Short-Circuit Protection Yes Over-Charging Protection Yes Over-Discharging Protection Yes Mercury Free Yes Interface 5.5 x 2.5 mm Battery Pack Form 4 x 18650 2 parallel and 2 serial Packing List 1 x Battery pack (67cm) 1 x Pouch