This SDS+ chisel set for use with heavy duty rock drill bits/chisels offers a very good selection of 10" chisels; two flat bits and one pointed bit. The appearance of the bits shows that they are of very high quality. I want to use them to drill a hole in a cinder block for an old electrical box, which needs to be done with enough precision for the box to fit properly in its hole and for the faceplate to cover the hole. Box and their electrical devices. Of course, I'll learn a lot more about their durability and strength from using them for their intended purpose.