Thread identifier for UNC and UNF

Many classic tractors use the old Unified National Thread - UNC Coarse series and UNF Fine series bolts and nuts.

These bolt often need to be sourced online, and hence it is important to identify the correct size and thread.

I made these following the guide at https://youtu.be/Wr4t-_Fg4CY?si=iJUK--cnAXa2WEOa I tested the threads shown on the picture, and they were perfect - so I expect they all fit.