Specifications:<br> Head Size Fit: M for 54-57cm(21.25-22.44in), L for 58-61cm(22.83-24.0in), XL for 60-62cm(23.62-24.4in)<br> Material: PC Shell + EPS Inner Buffer + Strap Polyester<br> Technology: Integrated<br> Internal Size: 17*22cm(6.7*8.67in)<br> Outside Size: 34*22*19cm(13.38*8.67*7.48in)<br> Weight: M-350g(0.77lb), L-380g(0.84lb), XL-390g(0.86lb)<br> Vents: 18<br> Certificate: CPSC 1203 + EN1078<br> Package: 1*Mountain Bike Helmet, 1*User Manual, 1*Sun Visor, 2*Screws<br> 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 sufficient protection to start your splendid adventure<br> SOLID CONSTRUCTION: Full Coverage Tough polycarbonate outer shell fusedhelmet'simpact-absorbing EPS foam layer for durability without excess weight, riding with free and comfortable<br> READ TO GO: Sleek design and diverse colors,it'scombined with 18 wind tunnel vents and internal channeling for heat dissipation during long journey riding<br> ACCESSORIES: With washable and removable padding inside, a big visor for sunlight proof and protects the head from small objects<br> 3 SIZE AVAILABLE: The rear dial for customizing circumference with the easily adjustable system, with3 sizesavailableit fits most youth, adults, men, andwomen'shead sizes