Box Four Prime 9 Derailleur (Black) (8 Speed) (Wide Cage) (Clutch)

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 rear derailleur boasts a limited-slip clutch with instant engagement and constant torque which prevents dropped chains and minimizes chain slap.

Features:

• Prime 9 Technology for less derailleur travel and better chainline, less wear, and improved lifespan
• Box’s “8 speeds is enough” derailleur
• Limited Slip Clutch 
• Stamped front/rear cage 
• Direct channel cable stay
• Bearing pulleys
• Not compatible with Shimano direct mount derailleur hangers (requires traditional derailleur hanger)