Base-Side Bevel File Guide SKS Multi Tool (includes file) Dial a precise angle from 0 degree to 5 degrees in 0.5 degree increments. It is recommended that you set the edge bevels with the file and then replace the file with 70-mm diamond stones to maintain the sharpness; if you always use the metal file, you will wear away the edge. The blue DMT or Red/Yellow Moonflex is a good choice, add the whole set if you are a racer. Bonus Benefit for this tool: If you don't know what base and side angles your ski/board are set to, this tool can help you find them. Before you start mark the metal edge with a sharpie, start the tool at the lowest angle and see if it removes the marking on your edge. Raise the angle step-wise and repeat until it removes the mark. That is your angle! Record the base/side angles for future reference.