DECENT FEATURES of the Grivel G20 Cramp-O-Matic Crampons A well known system which relies on a nylon speed lever in the rear Stainless steel front bale to hold the boot Quick to put on Perfect for plastic mountaineering boots that have a rigid sole and substantial heel and toe welts The stainless steel safety strap, which was invented by Grivel, is permanently mounted on the front bale Prevents total loss of the crampon should it be forced off the boot