The Shimano SLX CS-M7100 12-speed cassette is optimized with rider-tuned gear combinations for MTB excellence. Advanced shifting performance provides the confidence to enjoy any trail Light and stiff construction reduces cassette inertia resulting in faster acceleration and increased chain security HYPERGLIDE+ technology provides better chain engagement, stronger retention, and smoother pedaling with greater power and confidence over rapidly changing terrain Designed with a Shimano Micro Spline body that features smaller and more widely distributed splines to limit cog damage on freehub