The Metabo625368000 is an 18V battery pack with 5.5Ah capacity.These batteries are extremely long-lasting and durable thanks to their permanent electronic single cell protection ESCP and Air Cooled technology. They feature a capacity display with almost no self-discharge making them ideal for the most demanding applications. Features LiHD battery packs for ultimate performance and extremely long application with minimal temperature generation Ultra M technology Intelligent battery management for long-lasting battery packs Patented AIR COOLED charging technology Permanent Electronic Single Cell Protection ESCP when charging, for particularly long life Processor-controlled charge and discharge management Capacity display with almost no self-discharge