What you will need:
2.5mm Allen Key
There are two AFD options. The Freetour comes with the Alpine/GripWalk AFD installed. Each AFD works with boots that have the corresponding ISO sole. You can verify these numbers by looking at the bottom of the AFD, location indicated in red in the photo below.
To remove the AFD, unscrew the 2.5mm allen screws from the pedestal. Slide the AFD back off the pedestal. Slide the new AFD on. There are slots on the side of the pedestal that the AFD will slide onto. Re-fasten with the two allen screws.