Inspired by their legendary Base Camp Duffel, the Base Camp 200 winter boots are designed to keep you ultra-warm in the coldest conditions. The innovative 50/50 construction, which is partly made from lightweight ThermoBall™ that warms when wet, is a first-of-its-kind breathable down insulator that provides advanced thermo-regulation as you shuffle through the snow. So not only are these pull-on boots mega-toasty, but they harness high-performing Vibram® XS Trek EVO outsoles that provide the optimal balance of traction and durability, keeping your footing firm on unpredictable and wet terrain.