Perfect for flatter courses and time trials, the DURA-ACE C60 prioritizes aerodynamic efficiency and lateral rigidity.For the highest speed situations and the most powerful efforts, the redesigned DURA-ACE C60 wheel pairs a deep-section, all-carbon, tubular rim with an all-new hub design that cuts weight while enhancing drive rigidity. The C60´s construction places an extra emphasis on lateral rigidity making a sprinter´s dream.Features:- HR: High-Rigidity ver. +20% increased lateral rigidity for powerful riders and sprinters- 60 mm height full carbon rim- External rim width: 28 mm- DIRECT ENGAGEMENT- Compatible only with Shimano road 12-speed cassette sprocketsSpecifications:- Average weight: 770- Spokes_Straight pull: Yes- Brake type: CENTER LOCK disc brake- Axle fixing method: 12 mm E-THRU- O.L.D. (mm): 142- Rear speeds: 12- Thru Axle (Length x Inner diameter , mm)_142 x 12: Yes- Compatible spoke protector: CP-WR92C- D2 rim: Yes- Disc mount_140 mm Disc brake rotor compatible: Yes- Disc mount_CENTER LOCK: Yes- Front/Rear: Rear- OPTBAL (2:1): Yes- Reflector_AS: CATEYE RR-550-WUW SW- Reflector_DIN: CATEYE RR-317-WUA SW- Reflector_JIS/CPSC: CATEYE RR-550-WUW SW- Rim_Height (mm): 60- Seal_FREEHUB body: Contact- Seal_Hub: Contact- Spokes_Bladed: Yes- Spokes_Butted: Yes- Spokes_Number: 24- Tire_Recommended size: 25-28 inch - 32-28 inch- Tire_Type: Tubular- Wheel Size: 700C- Color_1 Hub shell: Series Color- Spline type_new HG spline(ROAD 12-speed): Yes- Engagement type: Direct engagement- Rim_External width (mm): 28- Spokes_Diameter (mm): 2.0-1.8-2.0- Specification: RTechnology:Center Lock:- The CENTER LOCK system makes an easy rotor installation possible with spline mount and a lock ring. The lock ring mounting system reduces the total working hours by shortening the amount of time of both installation and de-installation. In addition, the secure fixing by the spline mount enhances precision and rigidity while improving braking efficiency.D2:- Aerodynamic performance is affected by wind direction. To create the D2 rim, SHIMANO engineers considered both frontal and cross winds, aiming to achieve optimal performance in real-world riding conditions. Extensive prototype testing, in the wind-tunnel and on the road, proved that a wide rim shape with a deep tire bed performs best across a wide range of conditions. At yaw angles ranging from 0 to 15 degrees, the SHIMANO D2 rim profile reduces air drag better than others aero shape rims. This rim design also boosts lateral wheel stiffness and offers improved vertical compliance for increased control, comfort and durability on the road.E-THRU Axle:- The tool-less type thru-axle skewer system optimizes rigidity and weight balance and enables easy operation with a reliable internal cam mechanism. The 15 mm thru-axle system is 15% stiffer torsionally and 25% stiffer in transverse shear than a traditional 9 mm quick release front axle system. High rigidity is secured while keeping the optimum weight balance. The E-THRU axle hub system minimizes the distortion of suspension while maintaining lightweight for riding around sharp corners at high speed. An 8 mm thru-axle system for the trekking/hybrid hub and dynamo hub and a 12 mm thru-axle system for the rear are also available.Optbal:- The OPTBAL rear wheel spoke system features 21 spokes—14 on the drive side and 7 on the non-drive side. Cassette spacing in today's wheels produces unbalanced tension in traditional 1:1 spoke systems. This unbalance is intensified with the 11-speed cassette, producing nearly double the tension on the drive side spokes. Generally high and low tension spokes have respectively tendency toward breaking down and coming loose spoke nipples. Unbalanced tension affects durability and strength. The OPTBAL design rebalances spoke tension, enhancing wheel rigidity and strength for a more durable wheel.