Shimano CS-M9101-12 XTR Hyperglide+ 12 Speed CassetteSimply the bestShimano XTR 12-speed here and it's glorious. XTR has long been the golden standard in the mountain bike industry and now with it's support for massive gear ranges you'll be able to climb up the steepest of climbs. In order to get the most out of XTR you'll need an equally high end cassette. Enter the M9191 cassette which features Shimano's latest and greatest Hyperglide+ technology. Hyperglide+ drastically improves shifting quality, power transfer, and chain stability across the board. With a combination of steel, aluminum, and titanium gears, Shimano were able to shave as much weight off as possible without sacrificing durability, resulting in a shockingly low sub 367g cassette that'll last for countless miles. If you're hunting for the lightest and smoothest shifting cassette on the market for your 12-speed Shimano drivetrain then the XTR M9101 cassette is for you. FeaturesHyperglide+ technology delivers unrivaled shifting performanceOptimized steel, aluminum, and titanium gears save weight where possible without affecting durabilitySub 367g weight cassette is mind blowingly lightweightCompatible with Shimano Micro SplineSpecificationsCassette Body TypeMicrosplineCassette Cogs10-12-14-16-18-21-24-28-32-36-40-45T, 10-12-14-16-18-21-24-28-33-39-45-51TDrivetrain Speeds12Cassette MaterialAluminum, Steel, TitaniumWeight357g (10-45t), 367g (10-51t) | Shimano | CS-M9101-12 XTR Hyperglide+ 12 Speed Cassette 12 SPD, 10-12-14-16-18-21-24-28-32-36-40-45T