Box Two Prime 9 X-Wide Rear Derailleur
The Box Two Prime 9 Rear Derailleur is very similar to the Box One version however, to be more wallet friendly, it offers a non adjustable Tri-Pack™ Clutch, bushing pulleys and some muted finishes. Box Two rear derailleurs are still optimized for 11-50t cassettes and offer durability and performance for the most demanding terrain, just at lower price!
Worth the extra money
This is a fantastic derailleur. It is on par if not better then the Shimano XT and SRAM x01. What should make it better is the simplicity of a 9 speed v 12. If you’re looking at Box go with nothing less then this derailleur