The dovetail clamp is well engineered and fits the dovetail on the scope securely. The supplied counterweight weighs 1.5 kg and was far too heavy for my application so I used a stack of M12 penny washers instead. Note that the threaded counterweight bar is a 1/2 inch UNC thread rather than the usual M12.

This proved to be the solution to balancing my equipment. I have a William Optics ZS73 with field flattener, a ZWO guide scope and associated 120 mm mini camera, a ZWO electronic filter wheel, electronic focuser and ASI1600 MM Pro camera, two Astrozap dew heater tapes all mounted on Skywatcher EQ6-R Pro using 11inch ADM vixen bar. Prior to purchasing the counterweight, the balance point was right at the limit of the Mount's clamp, but is now central within the clamp's jaws and looks much more secure.