Strap into an evolution and welcome the Aircraft2. Developed in conjunction with athletes at the forefront of riding and racing like Sam Hill, the Aircraft2 takes notes from its predecessor, the Aircraft, and builds. Offering superior protection for when your routine gets off track with our proprietary Smartshock Technology, the most advanced helmet to date is ready for flight. FEATURES Carbon Fibre shell with Patent Pending injection molded chin bar integration. Smartshock® Rotational Protective System (14 point). Incredibly sturdy, full face downhill helmet. Multi-Density EPS foam injection molded with polycarbonate in 2 size specific molds (SM/MD & LG/XL). Massive airflow with a class-leading 20 ventilation ports. Multi-point adjustable visor designed for maximum vision and goggle stowage. Washable, moisture-wicking anti-microbial liner. D-Ring buckle for maximum security. The Aircraft 2 is tested and certified according to ASTM (F1952-15), CPSC (16 CFR 1203), CE (EN 1078:2012+A1:2012), and AS/NZS (2063:2008) Bicycle Standards. Click HERE for Aircraft 2 Crown Liners SIZE US SIZE EU CHEEKPAD SPARE CHEEKPAD CHEEKPAD COMPATIBILITY LINER SPARE LINER LINER COMPATIBILITY NECK ROLL SPARE NECK ROLL S 52 - 56 CM 28MM 24MM UNIVERSAL FIT 14MM 12MM S or M 20MM 25MM M 56 - 58 CM 28MM 24MM UNIVERSAL FIT 10MM 12MM S or M 20MM 25MM L 58 - 61 CM 28MM 24MM UNIVERSAL FIT 20MM 22MM L or XL 20MM 25MM XL 61 - 64 CM 20MM 24MM UNIVERSAL FIT 16MM 18MM L or XL 15MM 15MM