I recently bought a few machinist chests full of tools and other goodies. I'm not a machinist myself, but I'm familiar with a lot of the tools associated with the trade. This piece is a smooth solid steel cylinder with four equal spaced holes bored completely through it. It measures approximately 5.5" long and 2.25" diameter. Weighs almost 4-1/2 lbs. The end has stamped "Feb. 48 Eddie Champ." The other end is identical minus the engraving.
I suspect it might be a cylindrical square, but I've not seen examples quite like this. It came with a plastic sleeve.
Roller out of a machine for shaping sheet metal?
Shaping metal would need a more substantial central bearing, I assume.
Unless the bearings are on some sort of plates that lock into the 4 holes seen