・100% carbon rim with 50 mm height・Inner rim width: 21 mm・Rim profile shared with DURA wheels-ACE R9200"Improved aerodynamics.FeaturesEpic climbs, tight turns on the downhill or high gear on the flat, the new C50s represent the ultimate versatility in the new ULTEGRA R8170 wheel range. The tubeless carbon rim features a 21mm inner width that combines perfectly with wider modern tires, while the HYPERGLIDE cassette body is compatible with 11- and 12-speed cassettes.