This winter boot by MERRELL features Vibram Arctic Grip for traction and a waterproof shell with insulation for cold weather protection Details M Select DRY BARRIER impermeable membrane seals out water and lets moisture escape Full grain leather upper TPU wetproof shell for additional protection Metal hook and lacing eyelet for secure lacing Bellows tongue keeps debris out Gaiter D-Ring Snowshoe strap ridge for stability Fleece lining for added warmth 200 grams M Select WARM lightweight, low bulk insulation keeps you comfortable Kinetic Fit ADVANCED fleece lined removable contoured insole with reinforced heel cushioning for medium support EVA foam midsole for stability and comfort Molded nylon arch shank Merrell Air Cushion in he heel absorbs shock and adds stability Vibram Arctic Grip All Terrain outsole design for grip on wet ice and mixed winter conditions 5mm lug depth