With this model, Shimano and the cycling community celebrate the rebirth of the DA2 technology on their top of the range. And they do it at the highest level. Thanks to the latest generation wireless control, to a perfect functionality, to the 12 -speed transmission and the usual excellent construction quality, you can switch from one victory to another and put pressure on the competition. The fluid and precise gearbox has always been a Shimano trademark. This aspect was further perfected with the Hyperglide+boxes. The shape of the individual teeth is studied in such a way that noises or vibrations are almost not perceived during the passage to a larger or climbing pign. Despite this, the chain remains firmly, effectively avoiding possible slips. In addition, the time needed to change march has been significantly reduced. Shimano uses a combination of different materials for the construction of the box: while the smaller pignons, subject to lesser winding of the chain and larger load, are made of steel, the central ones are in titanium. The three larger pignons and the body of the box (spider) are instead in high quality aluminum. This use of materials based on the load guarantees uniform wear of the box and also extends the duration of the chain. In addition, it allows you to save weight significantly.