CYSKY 9 Speed Cassette 11 40T MTB Fit for Mountain Bike, Road Bicycle, MTB, BMX

Perfect replacement cassette suitable for road bikes, mountain bikes. Compatible with Shimano/Sram/Sunrace many brands system 9 Speed Cassette 11-40: 11T, 13T, 15T, 18T, 21T, 24T, 28T, 34T, 40T Cog Material: Nickel-plated, Carrier Material: High Tensile Steel About the shifting performance, we designed our tooth profile dedicatedly and use a narrow-wide tooth design to avoid the chain drop when back-pedaling. Close ratio gearing allows a more efficient use of energy through finer cadence control,easy to install without rear derailluer modification