Built for lasting performance, the Revel 4 Mid Height Snow Boot features waterproof, breathable protection and comfort-minded construction to keep feet happy mile after mile. made with a thermal heat shield inside to capture warmth and featuring a Speed lace webbing system, the womens Revel 4 Mid Height Snow Boot is built off KEEN's traditional wider footwear form. KEEN products are consciously created using a natural, pesticide-free probiotic-based technology called Eco Anti-Odor for breaking down odor in sweat, PFC-free water repellent (in applicable styles) and leather sourced from Leather Working Group (LWG) -certified tanneries.