Characteristics Fit system: 360 Fit System Lined: Yes Main product color: Black Adjustable fit: Yes Extended product color: Uranium Black Matt / Hydrogen White Color scheme: Monochrome Intended use: Adult Ventilation type: Fixed Construction type: Hard shell Head circumference range: 55 - 58 cm Helmet style: Open Sports headgear type: Helmet Activity: Triathlon cycling Ventilation: Yes Helmet shell material: Polycarbonate Suitable gender: Unisex Size (S/M/L): M Venting Location: Back vents, Side vents, Top vents