The Six Six One Evo AM Tres Helmet isn't like your old school trail helmet. Its lightweight design and clean graphics will have you never wanting to take it off. Unlike most helmets that are molded from EPS foam, the Evo AM Tres uses Contego foam. This foam is touted to absorb as much as 30% more impact energy than EPS, making it ideal for high speed situations and rocky, tree lined trails. To ensure that your helmet stays on, should you hit the dirt, Six Six One uses a Boa retention system to adjust the circumference of the inner webbing so that your head is securely wrapped.