The low-profile design of this helmet makes sure it is at home wherever you take it. An in-mold construction is used to keep the weight down while 28 vents make sure you are always cool and comfortable while riding. A quick turn on the Lazer Advanced TurnSys dial assures a snug yet comfortable fit that keeps the helmet firmly in place. Adjust it on the fly and start your cycling adventures. Key Features: Easy Vertical adjustability Diverse size range Eyewear friendly LED light compatibility Reduced plastics Weight: 250g Sizing: Head circumference (wrap a tape around your head about an inch above the eyebrows): S 52-56cm M 55-59cm L 58-61cm XL 61-64cm