Seam sealed waterproof construction. Waterproof full-grain and suede leather. Knit cuff. Removable 6 mm washable recycled felt inner boot. The midsole features a 2.5 mm bonded felt frost plug. Handcrafted waterproof vulcanized rubber shell with herringbone outsole, for slip resistance and shock absorbency. SOREL rated: -25° fahrenheit / -32° Celsius.