SAFETY FIRST: Our best-performance mountain bike helmet complies with U.S. CPSC and E.U.CE Safety Standards for Bicycle Helmets, offering versatility and maximum protection to start your splendid adventure SOLID CONSTRUCTION: Full Coverage Tough polycarbonate outer shell fused helmet's impact-absorbing EPS foam liner for durability without excess weight, riding with ultimate free and comfortable READ TO GO: Sleek design and dazzling colors, it's combined with 18 wind tunnel vents and internal channeling for heat dissipation during long journey riding ACCESORIES: With washable and removable padding and chin pad, Big Visor for UV and other elements protection 3 SIZE AVAILABLE: The rear dial for customizing circumference with the easily adjustable system, with 3 sizes available it fits most youth, adults, men, and women's head sizes Specifications: Material: PC Shell + EPS Inner Buffer + Polyester Lining Technology: Integrated Molding Head Size Fit: M for 54-57cm(21.3-22.4in), L for 58-61cm(22.8-24.0in), XL for 60-62cm(23.6-24.4in) Internal Size: 17*22cm(6.7*8.67in) Outside Size: 34*22*19cm(13.38*8.67*7.48in) Weight: M-350g(0.77lb), L-380g(0.84lb), XL-390g(0.86lb) Vents: 18 Certificate: U.S. CPSC, E.U.CE EN1078