This item is intended to be used as an adapter which allows various accessories to attach to the top of the Hi-Pod Tubes.

The black metal bar attaches directly to the third-party accessory via the standard quarter-twenty threaded screw.  Then the bar itself inserts into the mounting pedestal (round part which attaches into the top of the Hi-Pod Tubes and is secured by a ratchet).   You lock the black metal bar into the mounting pedestal with the two silver screws on the side. 

Note: The front metal head does not depress.  It is fixed.   The threaded screw in the middle can be removed.