The U1 2/5mm Venting Hooded Vest incorporates Waterproofs exclusive, Hood Air Venting System (HAVS) that uses a one-way valve to eliminate annoying air buildup and features a 5 mm double layered protection in critical heat loss areas. The hood features a 3mm smooth face seal for added comfort. The 2 mm anatomically sculptured under vest adds an extra layer of warmth under your wet suit. All seams are glued and sewn for extra strength and durability. Hooded vest comes in multiple sizes and is black in color. The hooded vest is made from durable nylon 2 neoprene.