The Shape 15mm Pair of Aluminum Rods (12" Long) connects into your camera rig, extends it and lets you add various Shape and third-party accessories compatible with 15mm rods. With these two rods and with a few fundamental accessories, you can most certainly even begin building your own rig from scratch. The rods are each 15mm in diameter, 12" long, hollow, non-threaded and made of reliable aluminum coated with a clear finish.