I like the Oster Spin Lithium Ion Dremel. It can be found on Chewy or Amazon. It's nice for the price, cordless and rechargeable, has two different speeds, works on dogs of all different sizes. I use it in combination with the safari nail clippers all the time at my grooming salon and enjoy it. Downside is it can be a little loud on the higher speed, so if you have sound-sensitive dogs I'd probably recommend a different one.
Rocket (pomeranian) - 01/2002 - 03/2016
Hircine vom HausReid "Sawyer" (GSD) - 11/24/16