Great choice! The Evo Vast Road Bike Helmet is perfect for cyclists looking for a comfortable and secure fit with optimal ventilation. With its FitRite easy fit retention system, you can easily adjust the helmet with one hand while riding. The 24 vents provide ample airflow to keep you cool during long rides. This helmet comes in two sizes: Small/Medium (51 - 55cm) and Large/X-Large (56 - 61cm).