Description: Underwater photo video double ball light arm is constructed to be durable and lightweight . It allows to expand your underwater photo video gear to your demands. This arm segment and two clamps since they do not need the same amount of flexibility as a still photographer does. The o-ring on the ball joints of the arms Used with small or large heavier strobes even in varying current conditions. The ball joint ball size and adapters is a standard 1" / 25mm. Specification: Material: Aluminium Alloy Size: 20cm/7.87inch (The Distance Between Two O-rings is 7.87 ”) Width: 2.4cm/ 0.94 inch Diameter of the Ball: 2.54cm/1 inch Weight (Approx.): 82g Package Includes: 1 Piece Dual Ball Joint Arm