This is a quick adjust clamp. It uses a washer on an angle to provide the quick adjust.

You will require

3/8 threaded rod any length
3 - 3/8 bolts
1 - 3/8 washer (outside diameter is about 1 inch)
2 - 5/16 washer (goes on the handle)

The 3/8 washer goes in the sliding clamp. The two 5/16 washers go between the handle and the stationary clamp. 2 nuts go on the end of the threaded rod. I used a hammer to damage the threads so that the nuts will stay in place. I then put the handle pointing up and put the threaded rod with the nuts on top and hit the rod with a hammer to drive the nuts and threaded rod into the handle. The nuts and threaded rod stay in place because of the 2 small tabs on the handle. The 3rd nut goes on top of the stationary clamp just to stop it from moving.