They work well in my cordless drill with bit holder, but when I use my 3/8" electric keyless drill to get more power, they jam the chuck wide open and it's a bear . to get free. This happened 3 times in a row and after a lot of nasty words I gave up, opened the drill chuck and went with the bit holder...although the drill bit is a little wobbly. Since they don't work well with my drill press I will buy a shorter set for them. These aren't bad drills, and because I hate throwing things away, I've given up my dusty Craftsman sets for good. They drill fast and clean but I wouldn't recommend them for a drill press unless you're using a bit holder and it's better to buy a set with a standard hex shank than a quick change like this. I would consider this a throw away set and when I get bored I just buy another set.