The size of crampon is restricted by the width of the ski. Of course if the ski crampon is too narrow it will hit the ski instead of the snow. Then again if the crampon is too wide the forces placed on the crampon/crampon mount increase and crampon failure becomes more likely. As a general rule you should not choose a crampon width that is greater that 10mm wider than the waist of the ski. The optimum crampon width is 7mm or less than the width of your ski underfoot. We recommend that you choose the ski crampon that closest matches the widest area of your mounting point, rounded up. In other words if your ski measures 104mm underfoot we would recommend our 110mm crampons. Our crampons come in a variety of common waist sizes which will help you get the perfect fit for your skis.
The listed size is generally 3 mm below the finished size. This extra space is to allow for normal variations in the crampons during manufacturing and to compensate for minor errors during the mounting process. Users desiring a tighter fit may choose to order a 95mm crampon for a ski with a measured width of 97mm, but this is about as tight as you should go.