The compact style and Advanced Rollsys System, make this an excellent fit. The Blade uses deep ventilation channels drawing air through the helmet, keeping the gap between head and shell to a minimum. 22 vents keep you cool and the weight low, so you can cycle in comfort. British Cycling Aeroshell is included. The detachable shell, without need for additional fixings, help improve this helmets aerodynamic performance, whilst also covering your head should the weather take a turn for the worse. The blade helmet combines great looks with high performance. Wear this helmet knowing you are helping to support british cycling and their cycling development programs, with a percentage of the sale of each helmet in the british cycling collection. 22 air vents. Head size from 55 to 59cm. Foam padding. Quick-release buckle fastening. Multicoloured. Manufacturers 2 year guarantee.