No clue

[GK1918]

I have had this unknown for many years and I know there should be some kind of wedge that is missing
I just would like to know what it is for. Came from wifes grandfathers box has to be from 1920-30s
when he was active hope this will attach sam

 

[GK1918]

I forgot to mention it fits perfectly on my compound SB 9

 

[aametalmaster]

It must be one of those home made contraptions that i have a drawer full of too. Back in the day the machinists just made what they needed for a certain job like i do today...Bob