Shimano never seems to rest when it comes to pushing the envelope in bike performance through technology. The already proven carbon laminate design of the Dura Ace wheel system still provides the riding character, aero advantage and quick accelleration of carbon fiber wheelsystems, but also has the huge benefit of the aluminum braking track to eliminate brake fade in wet weather and the fear of overheating a carbon wheel on long braking descents. Wider hubshells add even more rigidity and responsiveness, while the 50mm rim profile creates huge aerodynamic advantage even in crosswinds. Features: Aerodynamics performance Improved drive rigidity OPTBAL spoke system Lightweight within rigid Ultra-light full Carbon rim Efficient drive train For the performance driven triathlete and road racer Balanced low inertia & aerodynamics Wide section rim Front Specifications: Series: DURA-ACE Brake Type: Rim brake Over Locknut: 100 Axle Type: QR QR Skewer Length: 133mm Axle Length: 108 Rim Type: TUBULAR Rim Size: 622x17C Rim Height: 60 mm Rim Width: 22.4 mm Spokes: 16 Reflector (Option): CATEYE RR-550-WUW SW (JIS/CPSC), CATEYE RR-550-WUA SW (AS), CATEYE RR-317-WUA SW (DIN), Average Weight: 832g Rear Specifications: Series: DURA-ACE Brake Type: Rim brake Over Locknut: 130 Axle Type: QR QR Skewer Length: 163mm/168mm Axle Length: 141 Rim Type: TUBULAR Rim Size: 622x17C Rim Height: 50 mm Rim Width: 22.4 mm Spokes: 21 Reflector (Option): CATEYE RR-550-WUW SW (JIS/CPSC), CATEYE RR-550-WUA SW (AS), CATEYE RR-317-WUA SW (DIN), Average Weight: 1019g