I bought these for kitchen cabinet doors. I needed a 1/8" bit for drilling pilot holes for the new hinges and a 3/16" bit for drilling of holes The handles 1/8" bit broke on the third pilot hole! I was overwhelmed and had to run to a major hardware store to finish a new drill bit. The 3/16" bit worked great! It went through the tough oak like butter. would be the hardest. I keep the set as I've used the 3/16" bit so much, but I don't think so I will buy a Dewalt again.