The 12x Chorus cassettes for use with the disc or rim brake groupset.The Chorus groupset is fully compatible with the cassettes from the Record and Super Record 2x12-speed groupsets (11-29 and 11-32) but also introduces a new cassette specification of 11-34.The 11-34 cassette offers cyclists even more versatility and a greater choice and autonomy in terms of available gears. Chorus 12-speed now therefore offers a total of three cassette options:* 11-12-13-14-15-16-17-19-21-23-26-29* 11-12-13-14-15-16-17-19-22-25-28-32* 11-12-13-14-15-16-17-19-22-25-29-34Technologies* Same width as the 11-speed cassette: Totally compatible with wheels and frames.* The two bigger sets of three in a single-block piece: It eliminates energy dispersion.* Surface treatment: It increases durability and improves smoothness* Same-thickness spacers: Ensures error-free fittingFeatures and Benefits* Compatibility: Same width as the 11-speed, no need to change or update wheels* Smaller spaces: Faster, more precise shifting* Same spacers: Easy error-free fitting.* Sets of three in single-block steel: Stiffness and elimination of power dispersion* 25-29-34 set of three available as a spare part, * Can be converted from the 11-32 cassetteWeight: 306g (11-29 version)