Arkon's GN092L232T car or truck seat rail mounting pedestal is compatible with Arkon's Dual-T pattern universal smartphone and tablet holders (sold separately), including the Slim-Grip Ultra Universal Smartphone and Midsize Tablet Holder (SM060-2), Slim-Grip Universal Tablet Holder (TAB001), Universal Tablet Push Button Holder (TAB003), and Mega Grip Universal Smartphone Holder (SM040-2). This package is not a complete mount solution and includes only the Aluminum Seat Rail Mounting Pedestal with 23-inch Flexible Gooseneck. (Holders sold separately.) The seat rail mount is made of strong yet flexible aluminum, and is ideal for service vehicles, trucks, or those who need easy access to their devices but prefer mounting them somewhere other than the windshield or dashboard. Use a socket wrench to install the mount to the car's seat rail. Loosen the passenger seat track bolt, insert the included seat track bolt bracket (2 different brackets are included for various seat rail configurations), and then retighten the bolt. The seat bolt bracket openings measure 12mm wide and 30mm long. Bend the 23'' gooseneck and rotate the swivel ball adapter head for 360-degree rotation for exact positioning of the device.