Shimano Dura-Ace' computer designed Hyperglide (HG) sprockets incorporate specifically positioned shift ramps and tooth profiles for improved chain control during shifting. Shimano Dura-Ace' fast and responsive indexed shifting is the result. Shimano Dura-Ace is the only choice for the rider that needs the best
The sprocket width has been slightly reduced, to achieve chain compatibility and only increases the overall weight of the cassette sprocket by 17 grams more compared to the 9-speed CS-7700 sprocket. The CS-7800 Sprocket is compatible with the 9-speed freehub because it is designed to have nearly the same width. Sizes: 11-21, 11-23, (12-21, 12-23, 12-25, 12-27 +$19). 173g/11-23T