First of all. The bet starts at the first 1/4 inch and that's it. It took me 40 minutes to get through the 6 inch hole in the concrete. I switched to a 5/8 price from box stores. Put it on the same puncher. He cut right through. The drill application they give you goes in the middle of a 2 inch application, falls off, doesn't stay stuck. he unscrews. The so-called carbit, 2 inch part, needs to have all the studs all around, not just five on the entire part of the application. and there should be a 5/8" drill in the center, not a 1/4" drill. and must remain in the auction. But that's what you get when you buy china. I should have known, four offers for $21. nothing more needs to be said. don't waste your time. I needed 20 minutes. to get a quote from Stem. because it contracts a lot when you try to use it. That. Terrible, terrible. And believe me, I've been working on houses for over 30 years. I know bad tools.