The Shimano Dura-Ace CS-R9100 11-speed 11-30T cassette offers pro-level precision with a gear range wide enough for steep climbs and fast descents. Designed for road racers and serious riders alike, it pairs lightweight construction — with a mix of titanium and aluminum cogs — and Hyperglide tooth profiles for crisp, fast shifts under load. The 11-30T spread gives added versatility without sacrificing tight gear steps in the middle of the range, making it ideal for varied terrain or long mountain days. It’s a high-performance cassette that delivers smooth, consistent shifting for those who demand the best.