Tilos 3mm Neoprene Fin Socks for Scuba Diving, Snorkeling, Swimming, Watersports, Wading & Many More 3 millimeter neoprene keeps feet warm Nylon II neoprene is very durable and stretchy Blindstitched seams lay flat on skin, Seams glued to minimize water entry Honeycomb silkscreen bottom provides traction Makes a great liner for hunting or hiking boots!