The MID49 Baseline Bridgeplate for 19mm rods is compatible with standard ARRI dovetails and includes a lock and unlock lever for adjusting your camera balance along the dovetail plate. The locking lever can be extended to let you detach the baseplate directly from the dovetail rails, eliminating the need to slide it off from the back, although that option remains available. This lever lock system also allows you to mount the baseplate directly onto the dovetail rails without having to slide it from the back.