Lightweight, breathable with class leading performance and safety all with a modest budget in mind.100% ALTIS MTB HELMET - 2021 Deftly engineered for the demands of the modern-day mountain biker, the 100% Altis utilizes our proprietary Smartshock suspended rotational system coupled with 14 ventilation ports resulting in a safe, breathable, and budget-friendly trail helmet.Add in the adjustable visor for a cohesive storage of all 100% eyewear and goggles and you’re ready to hit the trails.Smartshock® Rotational Protective System (11 point) High Density EPS foam injection molded with polycarbonate in size specific molds (XS/S, S/M, and L/XL) Massive airflow with an impressive 14 ventilation ports Expanded coverage while still lightweight Multi-point adjustable visor designed for maximum vision and goggle stowage Washable, moisture-wicking anti-microbial liner Adjustable ratcheting fitment system Nexus push release snap-buckle Sizes: XS-S (53-56 cm) / S-M (55-58 cm) / L-XL (59-62 cm)