With a shallow-depth aero profile and lively acceleration, the ULTEGRA R8170 C36 wheelset is a climber´s delight that delivers performance every road rider will appreciate.With the speed and efficiency of tubeless tires, the everyday performance of a shallow, aero profile carbon rim, and the convenience of 11 and 12-speed compatibility, the new ULTEGRA R8170 C36 wheelset is an upgrade for any road bike.Features:- 36 mm height full carbon rim- Internal rim width: 21 mm- Shared rim profile with R9200 DURA-ACE wheelsSpecifications:- Average weight: 657- Spokes_Straight pull: Yes- Brake type: CENTER LOCK disc brake- Axle fixing method: 12 mm E-THRU- Internal grease sleeve: Yes- O.L.D. (mm): 100- Thru axle (length x inner diameter , mm)_100 x 12: Yes- D2 rim: Yes- Disc mount_140 mm Disc brake rotor compatible: Yes- Disc mount_CENTER LOCK: Yes- Front/Rear: Front- 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): 36- Rim_Requires rim tape: Yes- Spokes_Bladed: Yes- Spokes_Butted: Yes- Spokes_Number: 24- Tire_Recommended size: 25-622 - 32-622- Tire_Type: Tubeless- Wheel Size: 622 x 21C- Rim_External width (mm): 28- Rim_Internal width (mm): 21- Spokes_Diameter (mm): 2.0-1.6-2.0- Specification: FTechnologies: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:- 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.