Giro Selector Road Bicycle Helmet Closeout. Every second, every gram, every little detail counts...what's your Bicycle Helmet doing for you The Giro Selector Aero Bicycle Helmet is specifically designed with the latest innovations in aerodynamics and weight saving technology to boost your performance during time trials and triathlons. The niftiest feature of the Selector Bicycle Helmet is the modular tail section which allows the rider to choose between two different profiles. By combining a smooth front profile with either of two different lower tails, the rider can optimize the Bicycle Helmet for best aerodynamics based on their anatomy, riding position, and even course conditions. The removable eye shield works in tandem with the Bicycle Helmet's internal channels to keep you well ventilated while minimizing air resistance. Additionally, the Roc Loc TT retention system self adjusts to your head for lightning fast transition times.