ID this tool logo?

[Beerhippie]

This logo:



is the only marking on this 5 1/2" X 1/2" drive extension:



Any ideas? The closest I could find for the logo Diamond T was this:

Which ain't that close.

 

[930dreamer]

My search didn't turn up anything!

 

[Ricky Joe]

I think maybe old Thorsen.

 

[d42jeep]

I have some pretty old Thorsen and it doesn’t look Thorsen to me. Mr X has quite a bit of old Thorsen, maybe he has an opinion about that extension.
-Don