The Half Dome has long been a staple for climbers worldwide. Now redesigned, the helmet features a new lower profile suspension system with a one-handed dial combined with streamlined headlamp clips for added comfort and simplicity. Finally, an updated chin strap adds more efficiency and security while on the rock. EPS impact foam and durable ABS shell Updated, low-profile suspension system Streamlined, lightweight headlamp clips One-handed fit adjustment dial Easily adjustable chin strap Product Details Weight : [S/M] 330 g (11.6 oz) [M/L] 350 g (12.3 oz) Size Range : [S/M] 48-57 cm (19-22.5 in) [M/L] 55-61.5 cm (22-24 in)