It is a ZIM and 3/4" size

axle or flywheel " knocker"
You install it on the threads and strike it with a hammer while prying behind the flywheel.
Used to remove drums also on older cars , usually with wood wheels. 3/4" is probably to small for an axle.

Could be a flywheel knocker for a small gas engine.

EvilDr235-1/2

I used to loosen the nut until flush with the shaft and then hit it to prevent damage to the threads. Now I find out someone made pieces just for that, kinda like the lubrication socket set, I have led a sheltered hard life. ;-(

Not this one, but I remember using one (we called them drum breakers) on a 47 Mercury back in the old days.

That would be about right for steering wheels, too.