Muck Boot Arctic Sport Rubber High Performance Men's Winter Boot Synthetic Rubber sole Shaft measures approximately 11" from arch 5 mm neoprene provides comfort and flexibility, along with excellent waterproofing, shock absorption and heat retention properties; adjusts to your foot shape to resist blisters and chafing Completely sealed rubber shell extends up above ankle area for added protection from moisture Fleece lining is soft, durable and provides exceptional warmth in frigid environments; 2 mm of thermal foam under footbed; comfort rated from -40 F to 40 F (-40C to 4C) Outsole with rugged molded lugs for increased traction on slippery and uneven terrain 100% waterproof winter boots; EVA contoured, molded midsole for increased support