This is a very good hole saw set from deWalt. I found it very useful when renovating plumbing in a house. The kit includes a larger hole saw for making 4" pipe. I had to purchase the 4.5" hole saw separately and cannot be added to this kit. I understand that you don't often have to make a 4" hole, but it would be nice to have everything in one case. Another criticism is that with small hole saws it presses the hole saw against the bottom of the drill bit so hard that it is very difficult to unscrew it.