The Velbon QB-F51 Quick Release Plate is the standard replacement sliding quick release plate for the FHD-51Q Fluid Head and features an adjustable 1/4"-20 camera screw. Screw adjustement range is 1.9" (48mm).
A quick release plate can be kept attached to the camera's base at all times and allows the user to quickly and easily attach or remove the camera from the tripod without having to waste time fumbling with the threaded mount.