I was skeptical about this tool because of the thickness of the shank, and unfortunately I was right. I had 2 pieces of sheet steel that needed to be drilled out 3/4" to 1" to accommodate the larger screw. I used a standard (non-impact) drill bit with a standard 1/2" drive (spanner wrench). The first piece of steel was about 3/16" thick, and the Shockwave bit went through it like a hot knife. Oil. The hole was clean, and the floor was strewn with long cords of metal where the drill bit had neatly cut the edges into several loops. I had high hopes for the next piece. The second piece of steel was about 3/8" thick. As mentioned, there was there was already a 3/4" hole in the metal. Shockwave started to bite, but he clearly didn't like that part, and the movement was much slower. However, the first stage of the step drill cut when I pressed the bit. As the second stage touched the top of the part while the first stage was still going through, the drill stopped suddenly and the shockwave rod broke cleanly in two, leaving the drill firmly in the sheet metal with the rod still holding the drill in place.I can w Can anyone comment on the use of this bit in an impact driver or the durability of the edge or shank. For myself I will be looking for something with a stronger shaft and possibly a longer crotch.