Ultra Arm Double Ball (3") is a component of our Ultra Arm lineup which has a 25mm (1 inch) ball on each measuring 3 inches (76mm) from center to center. Great for building custom arm configurations! Key Features: - Also compatible with third-party 25mm ball mount systems - Ultra Arm Family Specifications: - Dimensions: 25.4 x 76.2 x 25.4mm ( 1 x 3 x 1 in) - Weight: 45.3 g (0.1 lbs) Highly Compatibility: Ultra Arm Double Ball components are interchangeable so you can use this arm in conjunction with the other options Wooden Camera makes like 1/4-20, 3/8-16, NATO Clamp, Hot Shoe, and Super Clamp. Ideal for attaching LCDs and lights: You can also add a center extension piece and a second Double Ball Clamp! Many existing 3rd party 25mm ball systems are compatible as well. Great for attaching LCDs, lights, audio recorders, and much more!