Transfer maximum power to the pedals. The Kestral Pro Boa ® combines our stiffest sole and clipless compatibility for an efficient all-mountain ride. The Boa ® Fit system means you can dial in a secure fit, while the wide Stealth ® C4 rubber sole provides confident footing in all terrain. Mesh inserts enhance breathability, and the quick-drying synthetic upper maintains all-weather comfort. Regular fit Boa ® Closure System for micro-adjustment, and secure and consistent hold Synthetic weather-resistant micro-perforated upper; Perforated EVA tongue with mesh overlay Textile lining; Stealth ® C4 rubber outsole for unbeatable grip Durable lightweight EVA midsole; Enjoy the comfort and performance of OrthoLite ® sockliner Clipless style; Non-slip heel cup; Stiff carbon-infused nylon shank