The lightest offering in Salewa's Pro Mountaineering Series, the Vertical Pro GTX Men's Mountaineering Boot is a tough, warm, and highly technical boot that's all about tackling winter alpine routes and crushing hard ice and mixed climbing. Its standout feature' Salewa's Flex System, which uses a key or a coin to adjust the flex of the nylon and fiberglass insole, taking it from completely rigid to semi flexible with a few quick twists, so you can cruise vertical ice and transition comfortably to glacier or ridge travel in a just a few seconds. Combined with the 3F system, which provides maximum lateral support, heel hold, and unparalleled ankle movement, the Vertical Pro truly provides one of a kind functionality for serious alpinists. Don't get fooled into thinking the Vertical Pro is some sort of novelty item, either it's tougher than a box of nails, with a Perwanger suede and Superfabric upper that'll stand up to crampons, ice tools, and rocks, and a full rubber rand for added durability. It's lined with a Gore Tex Duratherm XL waterproof and breathable membrane that features lightweight insulation, but just in case you're prone to cold feet, Salewa added the extra warmth and waterproofing of a super thin reflective aluminum layer. But wait, there's more! We haven't even mentioned the easy tightening 3D lace system that allows you to independently adjust the Vertical Pro in three different zones, ensuring the snuggest, most comfortable fit whether you're front pointing, flat footing, or passed out on the ground from exhaustion this would also be a good place to point out that the Vertical Pro is fully compatible with step in crampons. And, if you're not wearing crampons, the Vibram Salewa Pro outsole has ultra aggressive lugs for grip on mud and snow, and a climbing toe profile that's specifically designed to boost edging power and grip.