A lightweight full-face helmet with ASTM Downhill certification.The Leatt 1.0 DH is a full-face helmet with superior ventilation. The focus of this helmet is premium safety and great value. Featuring 360 ̊Turbine Technology, the helmet is lined with turbines which are 360 ̊moving discs constructed from an energy-absorbing shape and material, this tech has two exclusive advantages, namely the reduction of rotational acceleration to the head and brain and the absorption of energy upon impact at concussion level.Get full face head and brain protection at an amazing price. Downhill certified ASTM polymer shell in three sizesSuperior ventilationBrain injury reduction technologyReduces forces associated with concussionBreakaway visor function for additional rotational impact force reductionImpact foam for superior energy absorptionMoisture wicking, breathable and washable inner linerOptimal neck brace compatibilityCertified and tested: AS/NZS 2063:2008, ASTM F1952–10, EN1078, CPSC 1203360° Turbine TechnologyReduced peak brain acceleration by up to 30% at impact speeds associated with concussionReduces peak brain rotational acceleration by up to 40%Weight: From From 850g (1.8 lbs)Sizing: #S (55-56cm – 21 5⁄8 - 22”), #M (57-58cm – 22 ½ - 22 ¾”), #L(59-60cm – 23 ¼ - 23 5⁄8”), #XL (61-62cm – 24 – 24 ½”)