Clamp designed to perfectly clamp 2.5 cm diameter ball joints (like Carbonarm's ball joints) made of anticorodal aluminum and anodized to 40 microns (military standard) to ensure maximum durability and excellent resistance to wear and seawater. The two aluminum parts are joined by a stainless steel screw. On the inside, a stainless steel spring allows easy opening of the clamp when the handle needs to be loosened. On the outside, a washer and wing nut are placed to tighten the system easily. This system ensures perfect coupling and tightening of the ball joints to the arms.