Baffin Women's Avila Waterproof Boot 100% Neoprene Rubber sole Shaft measures approximately 5.5" from arch Heel measures approximately 1.25" Boot opening measures approximately 10.75" around Waterproof breathable membrane Removable multi-density insole Baffin's own B-Tek hollow fiber insulation for dependable warmth Rated to -4 degrees Fahrenheit making it ideal for rain, slush and snow Aggressive outsole with ample torsional rigidity for comfort and support