Specifically tailored for the demands of road cycling, this 12 speed chainset comes kitted out with carbon fibre crank arms for the best balance of stiffness, durability and low weight performance. Thanks to this model's carbon fibre build, it delivers a smooth and responsive pedal stroke without adding any unnecessary excess grams to your ride. Campagnolo has also equipped this model with a robust steel Ultra Torque axle and two aluminium chainrings for fantastic strength and reliability, wherever your next road journey takes you. Suitable for use with disc or rim brake groupsets, this chainset's chainrings also benefit from a special surface treatment for increased longevity. Carbon Fibre 12 Speed Road Chainset The updated Chorus chainset is a true concentrate of technology and versatility. Technically advanced thanks to unidirectional construction technology in carbon fibre, it is directly moulded without any surface coating and has an Ultra-Torque steel axle like the Record chainset. The revised 12x cranks are more versatile thanks to the bolt PCD of 123mm, giving it an extremely solid structure, also ensuring a wider variety of uses. The smaller bolt circle on the Chorus chainset makes it compatible with 36/52, 34/50 and the brand new 32/48 ratio chainrings (options available to select from the menu). Technologies: - The Q Factor remains the same (145.5mm): The widths and biodynamics of the stroke are the same. - Unidirectional carbon fibre cranks, steel axle and aluminium chainrings: Good stiffness and optimum power transmission. - Symmetrical teeth on the internal chainring: Fluid, precise transmission, even with extreme cross-chaining. - Optimised design for any chainring combination: Maximum performance, whatever the course style. - Double Fixing: Assembly of the large chainring onto the crank is secured by a ring of 123mm bolts, while the inner chainring is attached to the outer by way of 96mm PCD bolts. - Surface treatment of the chainrings for longer life. - 12x Chorus Ultra-Torque chainset for use with the disc or rim brake groupset. Manufacturer's Part Numbers: CPB820A Black Carbon 170mm 32/48T  CPB820B Black Carbon 170mm 34/50T  CPB820C Black Carbon 170mm 36/52T CPB821A Black Carbon 172.5mm 32/48T  CPB821B Black Carbon 172.5mm 34/50T CPB821C Black Carbon 172.5mm 36/52T  CPB822A Black Carbon 175mm 32/48T  CPB822B Black Carbon 175mm 34/50T  CPB822C Black Carbon 175mm 36/52T