The adjustable mount is sort of 'S' shaped and enables movement through 360 degrees. It attaches between the peg and the bracket. Picture a pedal on a bicycle. The main drawback with them is that they push the pegs out a couple of inches. I got rid of mine. You can turn the bracket round to sit in front or behind the highway bar depending on how long your legs are. Also by moving the bracket up or down on the highway bar you can also get some further reach adjustment. Hope that makes sense.