Giro Edition Snow Helmet Available in 3 In Form Sizes: S(52-55.5cm), M(55.5-59cm), L (59-62.5cm) In-mold Construction with Quilted Satin Interior 6 Wind Tunnel Vents, Adjustable Intake Port Vent System and Stack Vent Compatible with all after market TuneUps systems Compliance: ASTM F2040/CE EN1077