The O'Brien Flex V-Back Life Vest is made of lightweight Biolite material that's faster drying than standard neoprene. Designed with multiple hinge points for a comfortable fit, this vest features a flex V-back stretch panel and wide armholes to increase mobility and comfort. Zip closure and 2 concealed adjustable belts offer a secure fit. USCG approved type III.• Flex Fit stretches and wraps around the contours of your body• Split V-Back Stretch Panel for maximum maneuverability and comfort• BioLite construction is soft, lightweight, breathable, and eco-friendly• Zip closure with two concealed, adjustable belts for a secure fit• Belts stay out of the way• Multiple front and side hinges enhance range of motion• Wide armholes improve mobility• PWC lanyard attachment ring• U.S. Coast Guard approved type III• Men's chest sizes: XS(28"-32"), S(32"-36"), M(36"-40"), L(40"-44"), XL(44"-48"), 2XL(48"-52"), 3XL(52"-56") Multiple front and side hinges enhance range of motion Zip closure with two concealed adjustable belts for a secure fit USCG approved type III | Men's Flex V-Back Biolite Life Jacket