Gitzo “arca style” quick release adapter. This quick release optional adpater can be fitted on most Gitzo heads & replaces thew standard adpater or disc. It works with all Gitzo A & B profile plates & wih all 'arca style, dove tail' plates. The adapter's main features are the extermely wide adjustment range (from 37 to 74mm) & an anti-drop safety system that works with all Gitzo plates & many other (but not all) plates. It comes with two screw adapters (1/4'' & 3/8'') and