Possibly the worst tool I've ever purchased? Can't cut polycarbonate/abs blend plastic to save its life. I've never seen anything quite like it. See attached photo comparing this thing to a quality version (smaller diameter, but same basic design) made in USA (Made in U.S.A. is laser engraved right on the bit) by Milwaukee. Quite a difference, no? I mean, maybe I got a defective one? I guess I have to spring for the large Milwaukee bit after all. Should've known better?