It's all in the design. All Grub® are 100% waterproof keeping feet warm, dry, and protected in harsh weather and messy working conditions. The secret – our exclusive self-insulating waterproof CR-foam shell construction. The CR-foam bootie material acts as a "neutral medium" between inside and outside temperatures. Naturally lightweight, buoyant, and very comfortable, the material keeps the foot and lower leg warm and protected in cold and wet conditions.
Natural rubber overlays act as a protective skin for the upper bootie. The upper has a triple reinforced toe area and a quadruple reinforced heel area. The outsole is made of high abrasion natural rubber. The rubber in the boots will stay flexible for years.