The new Chorus groupset is fully compatible with the cassettes launched with the Super Record and Record 2x12-speed groupsets (11-29 and 11-32) and it introduces a new cassette specification (11-34) that will benefit the entire range of 12-speed mechanical drivetrains from now on. The new 11-34 cassette in fact offers cyclists even more versatility and greater choice and autonomy in terms of available gears. Mechanical groupsets with 12-speed transmission now therefore offer a total of three cassette options (11-29, 11-32, 11-34). Specification Same width as the 11-speed cassette Totally compatible with wheels and frames Smaller spaces - Faster, more precise shifting Same spacers - easy error-free fitting Size: 11-29T, 11-32T, 11-34T Chorus 12 Speed cassettes are compatible for use with both the disc and rim brake groupset Used the Same width freehub body as the 11-speed cassette, no need to change or update wheels Smaller spaces: Faster, more precise shifting Sets of three in single-block steel: Stiffness and elimination of power dispersion Same spacers: Easy error-free fitting 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 11-12-13-14-15-16-17-19-22-25-29-34 Technologies 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 fitting Features 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 cassette Weight: 306g 11-29 version Please Note: The new Chorus 12x 11-34 cassette is not compatible with Record or Super Record 12x groupsets