2009 Lazer 02 (OXYGEN) RD Road Matte Black Unisize Helmet 53-61cm 2009 Lazer 02 (OXYGEN) Road Matte Black Unisize Helmet 53-61cm Lazer O2 (OXYGEN) helmets feature the Lazer patented Rollsys fit system. Super Light Weight !! Weight 305g Fits: 53 - 61cm 21 vents with Patent-pending Rollsys fit system