What are the best SMALL hair clippers for a dog?

I have a 12lb powderpuff crested with a very thick wavy coat, but since he's so small most regular sized clippers can easily knick his armpits and just around any delicate area. I need to find some small but POWERFUL clippers (the size of a man's beard trimmer, with a blade no wider than 1.5 inches). I've used a wahl beard trimmer that I purchased at WalMart but it just didn't last.. and had trouble going through his thick fur.. and when we put him in a pony cut we give him the closest shave possible... so it definitely needs to be something little but powerful. Any recommendations??