The HD003 mounting pedestal can be used as a replacement, upgrade, or as an addition to an existing pedestal with a Dual-T pattern. It is compatible with Arkon's universal smartphone and tablet holders (sold separately), including the Slim-Grip Universal Tablet Holder (TAB001), Universal Tablet Push Button Holder (TAB003), and Slim-Grip Ultra Universal Smartphone and Midsize Tablet Holder (SM060-2). This mount includes only Arkon's Heavy-Duty Aluminum 4-Hole Drill Base Mounting Pedestal with 22'' Adjustable Arm and Dual-T Head (holders sold separately). Formerly an industry standard, the 4-Hole AMPS pattern consists of four holes located in a rectangular pattern spaced at 30.17mm by 38.05mm (measured as the center-to-center distance between holes). The 4-hole drill base mount is made of strong aluminum, and is ideal for environments where a more permanent solution is desirable, such as in a workshop or in retail. Screws are included. This mount can also be screwed directly into the floor of a car or truck. (Warning: Drilling into the vehicle's floor may damage the vehicle. Use caution and consult a mobile install professional to avoid drilling into any sensitive vehicle components.) Bend the 22'' adjustable arm and rotate the swivel ball adapter head for 360° rotation for exact positioning of the device.