Shimano XT CS-M8000 11-Speed Cassettes Steel construction on all but the largest aluminum gear Nickel-plated finish for corrosion and wear resistance Dyna-sys11 cassette with "Rhythm step" gearing for closer gear ratios and smoother shifting performance Fits Dyna-sys11 and current Shimano 9/10-Speed MTB hubs The largest cog is positioned inboard and above the drive-side flange. hubs with tall drive-side flanges may not be compatible due to spoke interference Cassette Body Type: Shimano Dynasys 11 Speed Mountain , Shimano/SRAM 8, 9, 10 Speed Cassette Cogs: 11-13-15-17-19-21-24-27-31-35-40 Cassette Cogs: 11-13-15-17-19-21-24-28-32-37-42 Drivetrain Speeds: 11 Range: 11-40 Color: Gray Defined Color: Gray