Shimano specifies this as the cassette of choice for their new M8000 11 speed XT mountain group. The entire cassette is nickel-plated for corrosion resistance and all but the largest cog are made from steel for superior durability. With 11 individual cogs the ratios are evenly spaced for predictable gear changes and each one is profiled to lift and move the chain while shifting. Since the M8000 cassette will slide onto any SRAM or Shimano 10 speed freehub body it is easier than ever to upgrade to an 11 speed drivetrain. Available in two gear ranges the XT M8000 cassette is the ideal compliment to an 11 speed XT or XTR drivetrain.