They are not 1/2" but 12mm and should be sold as such. Good otherwise, but annoying when switching from other tools, they are almost 0.030 inches lower. I would return them but I had to use them so now I have them I will adjust them. Edit February 29, 2020: I didn't realize this until I started cutting - they're magnetized. All of them. They are covered in chips. I checked everything with a compass, the boring bar is ok, the remaining holders are magnetized, I haven't been able to demagnetizeβ¦