Description: Compatible with cameras having the 1/4" mounting pattern Fits onto mounts accommodating the 25mm ball pattern This package includes only the 25mm Swivel Ball to 1/4" Camera Mounting Bolt Adapter. Secure the adapter onto any mount accommodating the 25mm ball pattern, then screw the camera on using the 1/4" mounting bolt The arm length is 50mm/2" Specification: Material: Powder Coated Marine Grade Aluminium Ball Size: 1" (25mm)Rubber Ball Package Includes: 1 Piece Motorcycle Ball Adapter Note: 1.We provide clear pictures, measurements where possible. Please check as much as possible to make sure the item is the one that you need. 2. Please allow 0.5-1 inch difference due to manual measurement.(1 inch=2.54cm) 3. Instruction is not included. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Please understand,Thank you