There are three basic body plate styles: Conventional, special, and bidirectional
Typically rectangular in shape and have contoured flanges that hug either the rear of the camera body, or the front, or sometimes both. All L-plates are also conventional plates (except B49L which is bidirectional). The dovetail on these plates runs parallel to the film plane or digital sensor to allow left/right adjustments. All conventional plates (but not L-plates) feature safety stop screws to prevent free-fall when camera is flopped over into the drop notch for vertical aspect. Orient the clamp channel side-to-side.
Special fore/aft plates
Usually a dovetail running in a front/back orientation, and have a flange that mounts to either the front or rear of the camera. They’re generally more suitable for medium format cameras that present a deep (thick) profile. All fore/aft plates feature safety stop screws at the rear. Orient the clamp channel fore/aft.
Square (1˝" square) and the dovetail runs the full perimeter of the plate (all four sides). This feature allows a bidirectional plate to drop into the clamp no matter its orientation. Bidirectional plates are not compatible with safety stops.
Arca-Swiss 35mm Mounting Plate
Prices below were obtained from average internet prices and may have
changed from the posting date