This carbide hammer is just what I need to drill deep holes in concrete. The shaft is very well made and hardly wobbles. After drilling many holes close together and heating the drill, the carbide tip was not damaged. I was very happy with it and I hope it lasts a long time. It also does a great job of getting all the dust out of the hole, saving time pulling the bit back and forth. The roundness of all holes was excellent (as long as I was drilling). Highly recommend and will buy again!