The Adapt-A-Post™ Side Track Base consists of a t-bolt, ratchet tooth and groove composition and female post spline hole. With a turn of the knob you can quickly fasten, adjust or remove the base to your existing track system. The ratchet tooth and groove composition enables you to slide and relocate the mount along the track; it can also rotate 360 degrees around, parallel to the track. The female post spline hole is compatible with many RAM Rod/Tube holders, along with 3rd party holders. Pressing of the side button, located on the right side of the image, you can quickly engage or release your holder from the base.