SP38MMCAM is compatible with cameras having the 1/4"-20 screw mounting pattern and fits onto mounts and shaft arms accommodating the 38mm (1.5 inch) ball pattern, including Arkon Robust Mount models and RAM Mounts Size C (sold separately). This package includes only the 38mm Swivel Ball to 1/4"-20 Camera Mounting Bolt Adapter. (Mounts, holders, and devices sold separately.) Secure the adapter onto any mount accommodating the 38mm ball pattern, then screw the camera onto the 1/4 inch-20 mounting bolt.