Designed for the canon 600mm f4 is and 400mm f28 is the wimberley ap 602 replacement plate lowers the overall height and centre of gravity of the lens making them easier to handle and pack they are manufactured to fit into an arca swiss style quick release clamp and also have 14 and 38 tapped holes for mounting to non quick release tripod heads and monopodsnote that as this plate mounts so close to the actual lens it is difficult to use it as a carrying handle in the same way as the incl