With the Shimano Dura-Ace CS-7900 Cassette 10-spd, shifting has been even further improved by creating an even more rigid (and lighter) aluminum carrier unit along with re-engineered teeth profile. Cassette design is lighter as Shimano has developed a super lightweight and rigid aluminum cassette sprocket carrier. The largest four cogs are titanium and weight is reduced by 10 grams.
Gear Ranges: 11-23 or 11-27,
Weight: 163 g. (11-23)