The Wimberley P20 Lens Plate is one of the finest lens plates available. The P20 size is designed for short to medium focal length telephoto lenses.
A lens plate such as the P20 is used to connect a tripod collar-equipped lens to an Arca-Swiss-compatible clamp such as those on a tripod head such as the Arca Swiss B1 Ballhead. The lens plate attaches solidly to the tripod collar on the lens and quickly installs into the clamp.
I also use the P20 to attach flash brackets such as the Wimberley ShapeShifter Macro Flash Bracket to a tripod collar on some of my lenses.
Since the P20 (and all other Wimberley Lens Plates) features a double-dovetailed design, accessories can be attached above or below the plate. The plate/clamp design creates a convenient and solid attachment setup. The P20 also features a pair of anti-twist nubs - to prevent the lens plate from twisting on the tripod collar.
The Wimberley P20 Lens Plate is solidly built and has a pair of stops on the end to prevent twisting. You can trust your camera and lens to stay put in this lens plate.