You love a good storm day as much as carving under blue skies. The Smith Altus ski and snowboard helmet lets you adjust the venting on the fly to match the weather conditions and your output. the lightweight in-mold construction makes for a one-piece design which is lightweight and durable for the confidence to get after it in any snow conditions, too. It's light enough for backcountry missions and cuts a classic profile. Specs Lightweight in-mold construction fuses the exterior shell and EPS foam for a one-piece design that's lightweight and durable Zonal Koroyd® coverage for lightweight, energy-absorbing and ventilated impact protection Certification: ASTM F 2040, CE EN 1077:2007 CLASS B Designed for ultimate integration with Smith goggles for maximum comfort and venting AirEvac™ ventilation system integrates with Smith goggles for fog-free lenses VaporFit Snow™ dial adjustment system offers 270-degree fit adjustment with the turn of a dial Removable, Aleck™ audio systems compatible ear pads Regulator climate control allows easy, one-handed vent adjustment XT2® antimicrobial lining offers sweat-activated odor control 10 vents M 55-59cm Round Contour Fit M 59-63cm L Race L 59-61cm Vida L