High-performance, purpose-built, waterproof protection for your feet. Premium stretch polyurethane is seam-sealed, fleece-lined, and reinforced at heel and toe for durability over seasons of use. Shaped for perfect it. 6mm waterproof zipper with Velcro® closure and a silicone-taped cuff help keep out water. Block System® technology increases zipper strength. Reflective inserts for visibility.