What is this cylinder like part? I found a pair of these among some parts I bought.  It looks like some sort of cylinder, which could hold an axle for a piston.

Is that correct, and how would I use it then?
This is one half of a "hydraulic" cylinder used like in the bucket of 7685-1: Dozer.

This element is Fric. Element, Cylinder and used often used in combination with Stick 6M W/Flange