Waterproof membrane seals out water and lets moisture escape Quilted ripstop and leather upper 105 grams Primaloft Gold Eco Series synthetic insulation Super Rebound Compound midsole with 15% recycled flecks provides durable shock absorption to help reduce torque and allow for a smooth transition into the midfoot Vibram Icetrek outsole designed to provide the improved grip on very cold, icy, or snowy surfaces