These Black Diamond Contact Strap Crampons are by far the best strap on crampons I have ever used. They are like comparing the driving experience of a Lamborghini with that of a Chevy. First, even though these are "one size fits all", they not only fit my hiking boots perfectly, they totally stay unwaveringly tight like a second sole. No matter how long I wore them or how much I kicked into the ice, they never showed any sign of loosening. I have already had them up above 10,000 feet on a dozen days of use. Second, they should really be called "Mountain Goats". They edge along an icy ledge like a miracle. If you have ever watched mountain goats taking seemingly impossible steps in the winter then you will understand what I am getting at. Never even one time did I have a slip or did the crampons fail to cut in for secure footing. Third, the ABS system just works. Like a champ. Although these crampons are not listed for technical use, I have found them to actually be quite good for ice climbing if you happen to be in a position where that is called for or you just chance upon a great climb when these are what you have with you. They really do stay incredibly tight and well fixed on your boots, no matter how much apparent abuse you kick at them. One piece of advice I would offer, which holds for all steel crampons, is to pack an adsorbent cloth in your crampon bag for drying them when you take them off. If you have the luxury of sunshine then set them to dry before putting them away. After damage due to walking over rock, rust is a real killer for steel. It is easy to guard against but just as with a tent, you will be sorry if you don't leave them dry. These Crampons will return your investment immediately. Just to wear such quality is a joy that can't be valued in dollars, but sprained ankles or serious falls can be guarded against by depending on such good gear.