The Shimano CS-M9101 XTR 12-Speed Cassette features a Beam Spider construction that uses a combination of aluminum, titanium, and steel to optimize weight savings, rigidity, and durability. It's only compatible with Shimano's Micro Spline freehub body and Hyperglide+ 12-speed chain. The cassette also features Hyperglide+ technology, which provides better chain engagement, stronger retention, and smoother pedaling over rough terrain.