BBB Maestro Helmet - Red Size M For maximum ventilation on all your rides. The HaloGuard construction gives strength and safety. A very aerodynamic helmet due to its compact profile.This helmet's unique Haloguard ventilation design which offers you optimal airflow at all speeds and due to its super compact shape it is still one of the most aerodynamic helmets of the peloton. Compact, strong and designed to make you the master of the roads.