100% waterproof. Stretch-fit topline binding snugs calf to keep warmth in and cold out. 5mm neoprene bootie with four-way stretch nylon. Extended rubber overlay for added protection. 2mm thermal foam underlay added to the instep area for additional warmth. EVA molded midsole with contoured footbed (internal). MS-1 molded outsole is rugged, aggressive and durable for maximum protection and stability. 16" High. 17" Shaft Circumference.