This is the new bi-directional P600
Perfectly fits:
Canon EOS 600D (without battery grip)
Anti-twist flange effectively prevents any pivoting between the plate and camera and/or lens.
International standard dove-tail plate, made of highest quality duralumin, is light-weight, low-profile, and strong enough to support your camera and lens system.
50W X 46L X 8H mm, 30 g (with mounting screw installed)