On some machines the bar is attached to a hinge on the lever, which causes swaying in the bar and the plates as the lever goes up and down. On other machines the bar is attached to a cable or belt, which runs through pulleys or over a wheel.
On some devices, the bar is attached to a pivot point on the lever, causing oscillation in the bar and plates with each movement of the lever. In contrast, other systems employ a cable or belt linked to the bar, allowing it to move smoothly through pulleys or over a rotating wheel.