Mares' Flexa DS 5mm Dive Boots are made from durable nylon-2 neoprene with a hard rubber sole to ensure grip on rocky and slippery surfaces. The strong zipper closure allows easy donning and doffing and prevents water entry. The Flexa DS 5mm Boots have an exclusive sole design that features a system of drainage grooves (DS) Draining System, which prevent the suction effect between boot and foot pocket which is common in other dive boots.