A Ledlenser lithium-ion rechargeable battery pack made up of three 18650 cells, rated 11.1 V and 3200 mAh. Packs of this type are used as the replacement or spare power source in Ledlenser's larger high-output lights, so a spare lets you swap in a charged pack and keep working. We could not confirm the exact Ledlenser article and its compatible models online, so please check the battery type and voltage in your light's manual, or ask us, before ordering.