Suitable for my drill chuck, core easy to clean. Just let your drill do all the work, even if you're stressed, don't try to rush the cut. I had to add 4 holes to an oak plywood aquarium cabinet, also had to enlarge 2 existing holes, worked very well, I made a 2 hole bracket out of standard 3/8" ply and used it to mount the existing 3 1/ 2 inches and to find the new holes needed the machine cut them all fine, towards the end I felt a little dull (oak veneer is stiff) but not too much, it still worked very well. With the extra holes and fans, the aquarium is much cooler.