Anyone know what this is ?
 

Picked up a crate full of tools yesterday at a yard sale. Has some great stuff in it, most is quite old. A lot of sockets, engine building tools, wrenches, and some odd stuff. In the pile was this thing I can not identify. Everything else i am sorting and cleaning right now.

http://s21.postimg.org/am2ztr4qf/IMAG4097.jpghttp://s27.postimg.org/8mmkob8yb/IMAG4098.jpg

Crimping die.

Thank you, i havent the slightest clue what to use it on, but now i can look it up.

It appears to be a crimping die. Normally there would be an O-ring around the groove in the middle to hold it together.

I thought it was part of a tail pipe expander

I think it's a Swage Tool.
Put a bolt through it and tighten it up, and see if it doesn't swell up.

?
 

it is a well used tail pipe expander missing the through bolt and washers