The edge trick with a diamond stone allows precision edge sharpening and repair on the snow. Precise angles at 0, 0.5, 1, 2, 3, 4, 4.5, 5 degrees. NOTE: This is a side-only edge tool; you only need to sharpen the side edge between tunes so this is a great touch up tool for travel or on the mountain tuning. Uses a 20 x 30 mm Coarse/Medium 325 grit DMT diamond stone. This stone is included with the tool and replacements are also sold here. This tool cannot be used to change edge bevels; it will sharpen and maintain the bevel that is set.