In a world full of knock-offs & duplicates, all batteries are not created equally. Dremel batteries are built for Dremel tools. Outstanding performance starts with power through the B815-01 12V 2Ah battery. At 2Ah, the B815-01 12V battery provides 2 amps of current per hour of use, giving your Dremel tool the life it needs to complete your tasks. Including 3 state-of-the-art cells in the B815-01 12V battery, the power output gives you the strength needed to cut, carve, sand, engrave, and more. This battery fits seamlessly with Dremel 8240, 8250 & 8260 models. Driven by technology, the B815-01 is built to protect against overheating, overload and unnecessary discharge for ultimate project efficiency. Lastly, having additional batteries can keep your project moving...use one while you charge the other...to help you complete your task without unnecessary stoppage or downtime.