Unknown Klein crimper? (help)

Hello, I'm new to this. I found these at a friend's workshop. Klein could not identify them. The handle totally reverses so one way is a smooth crimp and the other has the serrations. From browsing around it looks like the logo is from 1922 to 1933 or so. Apparently these were sold by Klein but on the inside of the handle (picture 3) you can see a ? ? FIN & SONS cast into it and a stamped D-9 next to it. I am totally lost as to what these were used for and if they are of any use to me today (I'd like to think so).