The Vanguard QS-47PF Plate Adaptor consists of the base and quick release plate. The base has a locking knob and a safety lock to make sure the plate will not be released accidentally. Two bubble levels are located on the base for aligning your camera to the horizon. The quick release plate has both 1/4"-20 and 3/8"-16 camera screws and a video pin. The base has a 3/8"-16 female thread and a 3/8"-16 Allen Bolt is included for attachment. Corresponding threaded holes on the side of the adapter allow you to store the screw that is not being used, so you can access it if and when you need it.