Box One Prime 9 X-Wide Rear Derailleur
SKUBX-DR1-P9AXWC-BK
The Box One Prime 9 Rear Derailleur takes the advantages of our legacy 9-speed drive-train but adds the advancements of a modern 1 by; a fully adjustable Tri-Pack™ Clutch, and an x-wide cage optimized for an 11-50T cassette. Forged construction steps up the durability and performance to an unparalleled level. Suited for the most demanding terrain.
IMPORTANT NOTES
- Prime 9 Technology™
- View Prime 9 Drivetrain Compatibility Manual
- How is the Ebike variant different?
- View Prime 9 Comparison Chart
- View Prime 9 E-Bike Comparison Chart
- Why Prime 9?

Box one
I had box two and loved it so I upgraded to box one. Still love it.


Love this thing
Can’t get enough!!!! Keeps me on trail for more miles with less issues

Better than the box 2
I'd like to add the box 1 shifter before my judgment!

gaspi
I am really happy with the Box One derailleur because it works so well! Fast and accurate, but must only work with cassette BOX two or one He doesn't understand much with cassette three and four. Cheers Gaspi