While everyone else keeps adding more and more gears, the Box Four Prime 9 Groupset takes a different approach. The engineers at Box decided that sometimes simple is better so they developed a groupset with a wide ratio range over only 8 cogs. The benefit is that fewer gears reduce the chain angle on the low end; making the chainline more direct across the whole range; improving component longevity and power transfer. The 2-piece multi-shift lever allows for shifting of 3 gears at a time. The rear derailleur boasts a limited slip clutch with instant engagement and constant torque which prevents dropped chains and minimizes chain slap. The Prime 9 chain is compatible with modern narrow/wide chainrings. Includes: Cassette (11-42 Tooth) Rear Derailleur Shifter Chain Specifications: Cassette Body Type: Shimano/SRAM (Not Compatible with XD or MicroSpline) Rear Derailleur Speeds: 8-Speed Rear Derailleur Max Cog: 42T Rear Derailleur/Shift Compatibility: Box Prime 9 Shifter Style: Thumb Shifter Speeds: 8-Speed Multi-Shift Color: Black