BOX  One Prime 9 X-Wide Rear Derailleur

Members, log in and use coupon code ANNIV24 at checkout to save 20% on this item thru 5/27. Exclusions apply.
Color: Black
Size: One Size
Shipping restrictions apply.

Members get an estimated $19.50 (10%) back on this item as a part of your annual .

Members get an estimated $19.50 (10%) back on this item.
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Don't shy away from demanding terrain. The BOX One Prime 9 X-Wide rear derailleur offers forged construction for top-of-the-line durability and performance for the most aggressive trails.


  • Adjustable Tri-Pack™ Limited Slip Clutch for exceptional chain tension and stability
  • Clutch force can be adjusted to give you the ability to tune your setup to the desired balance of shifter feel and chain retention
  • Impact-resistant, spring-loaded Pivot-Tech™ cable stay helps keep the cable, housing and you out of harm's way
  • Constructed with a forged aluminum cage, 3D forged aluminum linkages and a carbon-nylon composite knuckle for lightweight performance
  • Optimized for a 11–50T cassettes
  • Designed for use with standard derailleur hangers (not direct mount)


View the BOX Prime 9 Product LineView all BOX Rear Derailleurs

Technical Specs

Item #225265
Best Use

Mountain Biking

Derailleur Type


Cage Length

Long Cage

Max Rear Cog Size





290 grams

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