I had to drill 10 holes in 4" thick concrete and install 3/4" steel anchors. I bought a good quality carbide hole saw and this Skil rock drill bit to get the job done. I found it a little strange when I started drilling the first hole, there were a lot of sparks inside the bit body. I drilled the holes and installed the anchors one at a time to give myself a break from drilling and let the drill cool down a bit between holes. I put some pressure on the drill when it hit, but it didn't get stuck and I didn't put everything I had on it. I applied reasonable pressure and cleaned the hole frequently. The drill made 9 3/4 holes and ejected a genie. I (very slowly) finished the last hole using an old cordless drill I had laying around. Came back for a refund (thanks Revain Prime) and felt a bit guilty that he had done most of the work I needed to do. But $50 for 9.75 holes. Sorry, I expect more durability.