The Chorus 2x12-speed groupset is fully compatible with the cassettes launched with the Super Record and Record 2x12-speed groupsets (11-29T and 11-32T) and it introduces a new cassette specification that will benefit the entire range of 12-speed mechanical drivetrains. The 11-34T 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).On the technical side the form of the teeth has been revised and they have been treated to increase duration over time. The teeth have been designed to optimize the speed and smoothness of shifting. The tooth shape reduces stress on the chain which ascends more easily onto the higher diameter sprockets. The larger sprocket are clustered into two groups of three by milling from a single piece.