Safety stops at the front and back of our plates keep your expensive lens from accidentally slipping out of the quick-release clamp. If you wish to use only one or neither of these stops, simply remove them with the hex key provided.
The P-10, P-20, and P-30 plates have anti-twist nubs at the back of the plate. These help to keep the plate from twisting if it is mounted with only one fastener. The unique dual-nub design (as opposed to a single continuous flange) provides better performance when butted against a curved surface.