Dremel 7700 Series 7.2V NiCad Dual Speed Cordless Multi-Pro Rotary Tool Kit with 15 Accessories and 1 Attachment 7700-1/15 - The Home Depot
User manual Dremel 7700 (English - 88 pages)
Dremel 760-01 3-Hour Battery Charger for Dremel Cordless Rotary Tool Models 7700 and 7300- Battery not Included- Dual Voltage 4.8-volt and 7.2-volt - - Amazon.com
Hacking together a better dremel battery! - YouTube