Color Black + Yellow + Multi-Colored Brand Nitecore Model NL188 Quantity 1 Piece Material Li-ion polymer Cell Type Lithium Ion Battery Model 18650 Head Type Button Top Mark Capacity 3100 mAh Actual Capacity 3100 mAh Voltage 3.7 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 No Other Features With over charge over discharge protection; note: it's longer than usual battery without protection IC Certification CE UL RoHS Packing List 1 x Battery