The Manfrotto 2915 Super Clamp is made of lightweight cast alloy. The Super Clamp is a very versatile tool and it holds just about anything: cameras, lights, umbrellas, hooks, shelves, plate glass, cross bars, even other Super Clamps. In turn, the Super Clamp can be securely mounted on any tube from .5" to 2.1" and is supplied with a unique wedge insert for clamping onto flat surfaces. A built-in socket allows the use of over 30 attachments to hold anything from backgrounds to lighting fixtures. Note: The Stud (#03614) is not included. For this item with the stud, order #035RL. This item replaces old catalog #2915.