These are the 3.5mm Akona Low-Cut Molded Sole Scuba Dive Diving Boot River Booties Water Shoes They Feature: 3.5mm nylon II neoprene Glued and blind stitched seams for a superior water seal Airprene side panels allow for water to drain while providing protection and warmth Redesigned to provide a better fitting, warmer dive boot Rear panel runs all the way to the toe for increased durability Available in sizes 5 through 13 These fantastic boots are great for you next dive or they make the perfect tidepool/beach boot!