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

Back Order Now
You may back order this item and it will ship when it arrives.
Price: $68.99 (Save 20%)
Sale: $55.19

Please Log in to receive a notification when this item arrives in stock.

Save In List
This item earns up to 55 VIP Reward Points Learn More

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.


  • 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)

Speed: 8 Speed
Shifter Compatibility: Box Prime 9 (8 Speed)
Shift Mechanism: Cable Actuated
Max. Tooth: 42T
Min. Tooth: 11T
Chain Wrap Capacity: 31T
Cage Material: Aluminum
Chain Retention: Clutch
Color: Black
Weight: 328g

This product was added to our catalog on November 6, 2020

Box Prime 9 Model Comparison