The Supreme Hood is our hottest 3mm M-Flex (100%) neoprene hood, with wind skin side panels and Flaremesh lining on the inside, you won't ever have ice cream head again. All seams are GBS with waterproof stretch Flaremesh taping on the inside. The elastic adjuster tightens things up around the face while the small brim channels away water. The Double neck dam is designed to create a watertight seal against your wetsuit collar (the inner dam goes inside the collar and the outer fits over the collar.. or you can leave both over).