The Muckmaster High is Muck Boot's best selling commercial grade boot. This boot's stretch-fit topline binding snugs calf to keep warmth in and cold out. It has a 5mm NEOPRENE bootie with four-way stretch nylon, 100% waterproof, lightweight and flexible. The bootie has extended rubber overlay for added protection. 2mm thermal foam underlay is added to the instep area for additional warmth. The Muckmaster has an EVA molded midsole with contoured footbed (internal) and the MS-1 molded outsole is rugged, aggressive and durable for maximum protection and stability.