Bolle BACKLINE VISOR |Ski Helmet | Adjustable Ventilation| Removable Ear Pads| ABS Shell | 2 Interchangeable Visors Cat. 1 & 13[Key feature : Adjustable ventilation system] Choose between warm and cool, The adjustable ventilation system allows you to open or close vents with a simple movement [Adjustment system : Click to fit system] Adjustable fit to better match to your headsize, A fit system with a turnwheel that allows to fine tune the fit and comfort [Shell Construction : ABS hardshell] A robust and resistant construction, A strong ABS plastic hardshell provides