Durable mountain shoes for alpine challenges. The Viaz DFS GTX sets a new standard for versatile footwear for technical and fast mountaineering, demanding hiking, and via ferratas. They are an evolution of the AKU predecessor model Viaz and feature Dynamic Fit technology, which dynamically adjusts the tension in the heel area to your steps, enhancing comfort and stability. The AKU Dual Fit System (DFS) technology allows you to change the fit between walking and climbing modes. The Vibram Croda Litebase sole offers stability, grip, and precision, even in the most technical situations. The waterproof, breathable GORE-TEX lining protects your feet from moisture and ensures a pleasant wearing climate. Key features at a glance: Abrasion-resistant mountain boots for alpine tours, Dual Fit System provides an ideal fit, GORE-TEX membrane protects against moisture.