Ive got a Drill Doctor, i think its the 750, but not sure. It does up to 3/4 bits. You gotta love the ability to spit the point, they sure drill allot better that way. Got mine off of amazon.com with a free spare grinding wheel and free shipping. This is my second one, the first one only worked up to 1/2 bits. It will pay for itself really fast when your using the larger bits.