Looking for total control over device positioning? Our extension mounting arms are the perfect solution! These mounting arms extend from 8" to 10.5" or 10.5" to 15.5" in total length so you can dial in the perfect length depending on your vehicle, device holder and desired angle. How does it work? Simply twist the center collar to unlock the arm, extend or compress the arm to your desired length and twist the collar to lock it into place. 20mm Compatibility This extendable mounting arm features dual 20mm aluminum connector ends making it perfectly compatible with any of our dash mounts, 20mm AMPS balls and device holders with 20mm ball mounts. Strong & Lightweight Our telescoping mounting arms feature carbon fiber + kevlar construction with aluminum connector ends. They provide a rock solid connection between your dash mount and your device holder. Note: due to the presence of kevlar, the mounting arm has a subtle blue hue in direct light.