Discover the iBOLT 20mm to 25mm Dual Ball Mount Arm - the ultimate solution designed to bridge your mounting needs seamlessly. Engineered with sturdy aluminum and featuring a robust rubber-coated ball joint, this adapter is perfect for converting industry-standard 1 inch / 25mm and 20mm mounting systems. | The diameter of the ball joint is 1 inch or 25mm and the other side is 20mm. The measurement is not to describe the length of the entire adapter. Measure the diameter of the ball from the top of one end to another. | This iBOLT 20mm to 25mm Dual Ball Mount arm is made out of sturdy aluminum material and is compatible with all industry-standard 1 inch / 25 mm mounting arms. Ball joints are coated in a rubber material. | Commonly used as an extension arm with IBBZ-33921 or IBBZ-33791 and other industry standard 25mm / 1 inch and 20mm dual ball mounts/arms. Use with Bizmount series mounts or any other 1-inch / 25mm / B size industry standard compatible mount. | With the dual ball adjustments, this mount allows you to have the flexibility of rotating your device 360 degrees. | The length of this arm/adapter is 2.5 inches measuring from one end of the arm to the other and is made out of sturdy aluminum material.