Giros new high-end road racing helmet is the Aeon pronounced A-on & defined as a type of divine entity & it is the ultimate combination of ventilation & light weight smashing every other helmet out of the market Using cutting edge technology & design to enable an industry leading combination of weight ventilation fit & comfort Its Thermoformed SL Roll Cage is 49 percent lighter than the roll cage used on the Giro Ionos 24 Wind Tunnel Vents matched with deep internal channels ensures the best venting helmet in the industry Roc Loc 5 Fit System for the perfectly dialled fit without compromise Micro Tech Tri-Locs along with ultra-light slimline webbing enables the helmet to save over 36 percent of the weight of its fittings alone versus a standard performance road helmet X-Static padding for a plush fitting odour free helmet Smart details using metal badging Top spec pad-printed logos Available in 3 Super Fit sizes to the perfect Giro shape Certified to CE EN1078 Estimated weight for medium: 189 grams