This Ball Clamp with One-Side Cutouts and Ultra Blue T-Knob from Ultralight is used to connect light arms to underwater camera rigs, or arm sections to each other, using 1" mounting balls. The ball recesses on one half of the clamp have cutouts that allow the arm to be placed in virtually any direction. This clamp measures 1.5" between the centers of the ball recesses. The ultra blue anodized T-knob makes tightening and loosening the clamp easy, and it can be useful in the cinema industry for color-coding camera rigs.