The Barrel Clamp works on diameters from 42mm to 52mm. It holds a payload of 40kg on 16mm attachment and 600kg on 28mm attachment. The clamp is Tuv Sud certified for maximum safety for the user. It features 3 attachments: 5/8'' (16 mm) bushing, 1'' 1/8 (28 mm) bushing, and a 5/8'' (16 mm) spigot. This clamp is extremely strong, featuring a knob locking mechanism for better operation for the user and it includes safety cable.