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SKU: RRDR0490

BOX Three Prime 9 X-Wide Long Cage Rear Derailleur - 9-Speed, Matte Black, Sealed Bearings, Limited Slip Clutch, Versatile Compatibility with 11-50t Cassettes, Durable Steel Construction, Advanced Chain Management and Reduced Chain Slack

Regular price $83.99
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$10 Gift Card

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Description

Upgrade your bike's performance with the BOX Three Prime 9 X-Wide Rear Derailleur - the perfect combination of durability, versatility, and advanced engineering for 9-speed mountain biking and gravel riding. Designed with innovative features and premium materials, this derailleur ensures smooth, reliable shifting across a wide gear range, making it ideal for demanding terrains and versatile riding styles.

Premium Materials & Durable Construction

Constructed with a sturdy stamped front and rear cage, the BOX Three Prime 9 Rear Derailleur is built to withstand rough trails and extended rides. Its robust design promotes longevity and consistent performance, even under heavy loads and harsh conditions.

Performance & Engineering

The Prime 9 technology provides a gear range comparable to 12-speed drivetrains, offering riders a broad selection of gears with fewer shifts for simplified operation. The sealed bearing pulleys reduce friction and promote smooth, silent shifting, while the direct channel cable stay enhances cable tension management for precise gear changes.

Innovative Components & Technology

Equipped with a limited slip clutch, the derailleur engages instantly to maintain chain tension, greatly reducing chain slap, preventing chain drops, and improving chain engagement on rough terrain. This clutch system provides constant torque, ensuring your chain stays secure during aggressive riding. The wide compatibility with 11-46 and 11-50T cassettes makes it one of the most versatile options for Prime 9 drivetrains.

Style & Use Case

Featuring a sleek matte black finish, this rear derailleur complements a wide range of mountain, gravel, and adventure bikes. Its long cage design allows for a larger gear capacity, making it ideal for trail riding, enduro, or bikepacking adventures where gear versatility and durability are crucial.

Key Features at a Glance:

- Compatibility with 9-speed cassettes (11-46T and 11-50T) for maximum versatility

- Prime 9 technology delivers the gear range of a 12-speed system with fewer shifts

- Integrated limited slip clutch reduces chain slap and chain drop during aggressive riding

- Sealed bearing pulleys ensure smooth, maintenance-free operation

- Direct channel cable stay for precise, consistent shifting performance

- Sturdy stamped cages built for durability in tough riding conditions

Upgrade your bike with the BOX Three Prime 9 X-Wide Rear Derailleur for superior shifting, increased reliability, and a rugged design tailored for mountain, gravel, and adventure riding. Experience smoother rides and greater control with this high-performance derailleur engineered for riders who demand the best.

  • Enhanced durability with sealed bearing pulleys and a robust stamped aluminum cage, ensuring long-lasting performance in tough riding conditions.
  • Advanced Prime 9 technology provides a wide gear range comparable to 12-speed systems, allowing for versatile gear options on MTB and gravel bikes.
  • Includes a high-performance limited slip clutch that minimizes chain slap, improves chain retention, and delivers consistent power transfer during aggressive riding.
  • Compatible with a broad range of cassettes from 11-46T to 11-50T, offering excellent flexibility for personal customization and different riding terrains.
  • Sleek matte black finish combined with innovative engineering features like direct channel cable stay for smooth, reliable shifting and modern style suited for mountain, gravel, or adventure cycling.
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We pride ourselves on our ability to ship and deliver your gear with excessive speed! We ship from 22 locations throughout the United States and most orders will arrive in 3 days or less with Free Shipping on orders over $75!

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Most orders placed during the workweek before 1:00 PM Eastern time ship the same day, but during peak/holiday season or depending on inventory location handling time can take up to 48 hours. If you have questions regarding shipping estimates, don't hesitate to get in touch with us before placing the order. There is a direct signature requirement for all orders over $500.

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365 Cycles puts the customer above everything. Our number one goal is your satisfaction. When you press the shift lever you want the gears to shift, and when you buy bicycle parts, you want the bicycle parts to arrive on time in new condition. With over 60,000 products and 22 warehouse locations throughout the country, we have the parts you need and they are coming in hot!

Living an active lifestyle is just that, a lifestyle that never goes away and our goal is to always exceed your expectations so we can take this lifelong journey together. We strive to have the parts you need, at competitive prices with unmatched shipping speeds!

If there is ever an issue with an order we will work at warp speed to fix our mistake and make sure you never go a day without a bicycle! If you are not receiving the quality of service you need from one of our exceptionally qualified bicycle experts, tell them Ben Berman told you to tell them "Customer Loyalty" and then name your terms.

Our team is waiting to help you 7 days a week and they are more qualified to help than I am but if you ever feel like you're not getting the service you need I’m personally asking you to email me at ben@365cycles.com with "CUSTOMER LOYALTY" in the title and I will personally handle your order.

Over the years we have served millions of satisfied customers and continue to serve many of them today. With your feedback, we are confident we can take this lifelong journey together and build a friendship that goes beyond parts and accessories.

“If you want to go fast, go alone, if you want to go far, go together.” -Someone Smart

Ben Berman Founder & CEO of 365 Cycles


Company Core Values: 

These were established by the members of our team and we use them every week to call out team members who have shined in one of these areas. Feel free to let us know at info@365cycles.com if someone you worked with has gone above and beyond in one of these areas. 

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If it is to be, it’s up to me" You are personally responsible for controlling the outcome.

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Stronger together:

If you want to go fast, go alone, if you want to go far, go together. Get your team involved and become stronger together.

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