Features Glacier Trek™ SPK outsoles with 16 replaceable cleats embedded in the sole to help maintain traction in the harshest winter conditionsThe rugged but lightweight outsoles provide excellent slip resistance on ice and snow while the insulation and internal bootie keep your feet warmSpecially formulated rubber remains flexible, even at sub-zero temperaturesEquipped with an adjustable instep strap for a secure, quick fit500 denier nylon upper fabric with waterproof membrane4mm polyurethane foam insulation for additional warmth2.5 mm polyurethane internal bootie100% waterproofTighten cleats with included cleat wrench before wearing outdoorsIf wearing over a work or combat boot, select one size up