Spherical Technology, Powered By MIPS Impact Management Construction: Independent, In-Mold Liners With Spherical Ball-And-Socket Design, Polycarbonate Shell, Hardbody Lower Shell 15 Wind Tunnel Vents With Internal Channeling, Roc Loc 5 Air Fit System Product Weight: 270 (Size Medium CPSC, CE) Certification: Complies With The Us CPSC Safety Standard For Bicycle Helmet For Persons Age 5 And Older, E.U.: CE EN1078