Hey guys I have a auction today and they have a lot of geometric die heads for sale that I don’t know the differences between. They must have ten of these tools they look to be different sizes from the pictures not the arbor but body size. They also have bins of the thread chasers, and a grinding jig for the chasers. I e heard of them and seen people use them but I don’t know about them. Do you need multiple sizes for a range of threads? Metric/standard? Any info would be appreciated thanks.