Protected, button top. Sold individually. This is a super high capacity 26650 battery (~26700 effective length). Performs well in devices up to 8 amp draw (protection circuit limited); however, the King Kong 4000mAh cell has better voltage sag characteristics for flashlights that draw about 4 amps or more, so if your flashlight is drawing a lot of juice and you care more about peak output vs. runtime, then choose the King Kong cell. If you want the most runtime possible, then this is the cell you want.