The XX SL Eagle Transmission (T-Type) cassette is a key reason why Eagle Transmission offers the best inboard and outboard shifting performance under load. Thanks to its full X-SYNC design, the stronger you pedal, the better the shift. This is the lightest Eagle cassette ever, as well as our most precise and durable. Its new generation features a fully machined hardened steel X-Dome architecture for gears 1-9 and an ultralight fully aluminum Spider Cog for gears 10-12. Designed as integrated and interdependent transmission components, the XX Eagle transmission cassette and derailleur make direct contact, ensuring perfect alignment on every bike. From its massive 520% gear range, the 52-tooth gear drops with better gear progression with 44 and 38-tooth gears in the lower range (compared to the 10-52 tooth Eagle transmission cassette).