Anti-Fatigue Technology: a comfort system designed with shock-absorbing, geometrical technology that returns energy back to the foot to deliver all-day support and comfort. Vibram Rubber Outsole: built to withstand the harshest working environments. Waterproof Seam Sealed: footwear includes waterproof leather for durable waterproof protection. Insulated: Thermolite, lightweight, non-quilted, quick-drying, moisture-resistant insulation helps keep feet warm in any weather. ReBotl: lining materials that are made with at least 50% recycled polyester.