Shimano Ultegra Di2 Shadow rear derailleur. - Sleek integrated appearance - New low-profile design - Shimano Shadow RD - Race endurance - Optimized slant angle - Maintain race concentration with more intuitive shift control - System communication with front derailleur - Shimano Synchronized Shift - Wide compatibility - Short cage covers: 11-25T to 11-30T - Medium cage covers: 11-28T to 11-34T - Average Weight: 242 grams (SS type), 249 grams (GS type)

The Shimano Altus RD-M310 rear derailleur is a quality, durable replacement rear derailleur for 7 and 8-speed drivetrains. - 13t upper and 15t lower pulleys - Maximum cog size: 34t - Total capacity: 43t

M21 rear derailleurs are designed to work with 6- and 7-speed Shimano road and mountain shifters. Enjoy the wide variety of bikes you can get going again with M21 rear derailleurs. - Robust composite and steel construction - Compatible with Shimano 6- and 7-speed mountain and road systems

The new TR12 rear derailleur is able to provide a quiet and accurate ride over the roughest trails. The key feature to this pursuit is the Hall Lock. During the Race season, lead mechanic for Intense Factory Racing, John Hall, noticed excessive movement around the B-knuckle when riding over rough rock gardens and in tracked out corners. This was leading to more chain skipping and slapping creating possible variances in shifting. This inspired John's idea to lock the B-knuckle to the bike's derailleur hanger. TRP engineers worked closely with Hall to create this feature, The Hall Lock. - Hall Lock - G-Spec Ratchet Clutch - G-Spec finishing touches - Carbon fiber cage & upper link - Extra-wide parallelogram pivot - Sealed cartridge bearing pulleys

With an integrated chain stabilizer mechanism, the Shimano GRX derailleur provides a quieter experience along with shifting security and precision on mixed terrain. For rides on smooth surfaces, the derailleur features and ON/OFF switch for the chain stabilizer. The RD-RX815 Di2 version offers the digital precision of Shimano electronic shifting with synchronization and is compatible with road cassettes with a max cog size of 34T. - Adjustable, gravel-tuned chain stabilizer prevents chain slapping and drops - Switch stabilizer ON/OFF to match the terrain - Total capacity: 38T - Smooth and reliable mixed surface shifting - Compatible with current road Dual Control Lever - Maximum front difference: 17T - High cog: Max. 11T/Min. 11T - Low cog: Max. 34T/Min. 30T

SRAM's Force WiFli Rear derailleur is made for wide-range 2x10 systems. Its long cage can handle an 11-32 cassette! You get the huge gear range of a triple with reduced weight and better shifting. Of course, the WiFli still uses SRAM's renowned Exact Actuation technology for precision shifts every time. Plus, the Force is crafted with cutting-edge materials, such as a super-light carbon cage and a magnesium inner link for feathery low weight, flawless shifting and reliability.

SRAM's X5 9-Speed Rear Derailleur provides precise, dependable shifting along with long-term durability. Its aluminum construction keeps the weight down, while SRAM's 1:1 actuation ratio and direct cable routing provide quick, reliable shifts.

The Box Three Rear Derailleur simplifies the features found on the Prime 9 Box One and Two rear derailleurs making for a fully featured wallet friendly rear derailleur. Including a Limited Slip Clutch, Sealed bearing pulleys and a solid construction Box Three Rear derailleurs are compatible with 11-46 and 11-50t derailleurs making it one of the most versatile derailleur offerings for Prime 9.

With SRAM's RED Rear Derailleur, SRAM set out to make their already race-proven design lighter, faster, and quieter. Through careful analysis of design, material selection, and component integration, they achieved all three. Refined shaping and a hollow titanium fixing bolt lighten the overall weight while maximizing performance. Carefully sculpted jockey wheels work together with the new chain pulley cage for lightning-fast, ultra-precise shifts. An updated elastomer coating applied to the jockey wheels makes for extra quiet operation. Plus, a redesigned shift cable routing makes set-up and adjustment easier than ever! Light, fast, and quiet, the RED derailleur delivers!

Incredibly fast, astonishingly quiet and impressively precise — fly through all 11 gears with SRAM's Force 22 Rear Derailleur. It takes advantage of SRAM's Exact Actuation technology for precision shifts every time. Carefully shaped jockey wheels work together with the sculpted chain pulley cage for lightning-fast, ultra-precise shifts, and an elastomer coating applied to the jockey wheels makes for extra quiet operation. A carbon outer cage, aluminum inner cage, and magnesium inner link keep the Force 22 at a svelte 178 grams.

Incredibly fast, astonishingly quiet, and impressively precise — fly through all 11 gears with SRAM's Force 22 WiFLi Rear Derailleur. It takes advantage of SRAM's Exact Actuation technology for precision shifts every time. Carefully shaped jockey wheels work together with the sculpted cage for lightning-fast, ultra-precise shifts, and an elastomer coating applied to the jockey wheels makes for extra quiet operation. A carbon outer cage, aluminum inner cage, and magnesium inner link keep the Force 22 WiFLi at a svelte 190 grams. The WiFli version shifts up to a 32T max cog for a super-wide gear range.

On any surface you can imagine, in any drivetrain configuration, the Rival eTap AXS rear derailleur will handle it. Secure chain management and fast, precise shifting make for a smooth and quiet ride, every time. - Wireless electronic eTap shift logic for intuitive shifting, easy setup, and reliability - Compatible with both 1x and 2x drivetrains - 36T cog max derailleur works with 10-28T, 10-30T, 10-33T, and 10-36T cassettes - SRAM AXS-enabled, allowing easy personalization - Spring clutch keeps the drivetrain quiet and secure - X-SYNC pulleys for increased durability and efficiency - 36T max rear cog - Battery Not Included

The heart of this microSHIFT Acolyte derailleur is the innovative SpringLock system. By pairing a customized linear rate high tension spring and a dual stage activation mechanism, we’ve developed a system that can provide substantial chain security when you need it and can be turned off when you don’t.  To engage the clutch, turn the engagement bolt clockwise until it clicks. There’s no way to overtighten the bolt. To disengage the clutch for wheel removal, flip the switch. It’s that simple. - Innovative SpringLock chain retention keeps chain in place over rough terrain - Direct path cable routing for smooth and responsive shifting - Compatible with 12-42T and 12-46T 8-speed cassettes - Compatible with Acolyte shifters only

Find new ways to enjoy trekking and daily flat-handlebar riding with this reliable rear Shimano CUES RD-U6020 Shadow derailleur's seamless shifting and pedaling. Its low-profile design and chain stabilization give riders the confidence to choose rougher routes. Plus, e-bikers will benefit from reliable, long-lasting performance thanks to its eBike rated design. - Stable drivetrain performance on trails, gravel, and city streets - Shadow low-profile design protects rear derailleur from obstacles in a wide variety of riding scenes - Designed and tested to provide enduring e-biking performance - 11t upper and 13t lower pulley wheels - Compatible with LINKGLIDE AND HG 11-speed chains

This new NX Eagle derailleur features the proven SRAM 1x-specific X-HORIZON design. The larger, 14-tooth X-SYNC lower pulley easily facilitates 11- to 50- and 10- to 50-tooth cassette capacity, and also adds to NX Eagle's overall smooth-pedaling feel. The Type-3 ROLLER BEARING CLUTCH provides quiet, consistent performance and durability. - Eagle technology provides an expanded, optimum, gear range making you fast on the flats, giving you control on the climbs and unleashing your speed on the descents - Eagle is a complete drivetrain system that was developed to be an integrated high-performance ecosystem. The engineering and testing that went into the development provide for maximum performance, safety, and long-term durability to ensure a great consumer ride experience. We guarantee this performance when Eagle drivetrains are used as a complete ecosystem. For additional information, please contact your SRAM Sales Contact. - Completely new rear derailleur incorporating our proven X-HORIZON design and new Type-3 ROLLER BEARING CLUTCH technology - Eagle ecosystem-engineered mounting system and CAGE LOCK positioning add robustness - Eagle pulley technology provides greater efficiency, crisper shifting and quieter operation - Speed (RD): 12s - Cable pull ratio: X-actuation - Cage (RD): Long - Max tooth: 50 - Color (RD): Black - Pulley bearings material: Steel - Cage material (RD): Steel

Shimano's 105 Rear Derailleur delivers high-end function with upscale looks. With a body of light, durable cold-forged aluminum in Shimano's wide-pivot design with their light-action spring, rear shifting is practically effortless and always super smooth. The top pulley stays a uniform distance from each cassette cog ensuring that every shift resonates with the plunk of exact gear engagement.

Shimano's Tiagra Rear Derailleur GS (10-speed) is sleek, balanced and consistent. The Tiagra 4700 series provides serious entry-level riding performance with trickle-down technology from the top shelf Dura Ace line. - Model Number: RD-4700-GS - Series: Tiagra - Cassette Compatibility: 10 - Maximum Sprocket: low sprocket: 34T / top sprocket: 12T (front double) / 20T low sprocket: 32T / top sprocket: 12T (front triple) - Minimum Sprocket: low sprocket: 28T / top sprocket: 11T (front double) / 20T low sprocket: 25T / top sprocket: 11T (front triple) - Maximum Front Difference: 16T (front double) / 20T (front triple) - Total Capacity: 39T (front double) / 41T (front triple)

Shimano Tourney TX is a basic 8-speed rear derailleur for entry-level sport bikes and riders. Enjoy durable, trouble free, and stable performance. - Maximum cog size: 34t - Total capacity: 43t

With SRAM's WiFLi RED Rear Derailleur, SRAM set out to make their already race-proven design faster, quieter, and able to accommodate a full 11-32 cassette for a huge gear range. Through careful analysis of design, material selection, and component integration, they achieved all three. Refined shaping and a hollow titanium fixing bolt lighten the overall weight while maximizing performance. Carefully sculpted jockey wheels work together with the new chain pulley cage for lightning-fast, ultra-precise shifts. An updated elastomer coating applied to the jockey wheels makes for extra quiet operation. Plus, a redesigned shift cable routing makes set-up and adjustment easier than ever! Fast, quiet, and capable, the RED derailleur delivers!

The Campagnolo Super Record EPS 12 speed rear derailleur offers improved shifting performance with a trajectory curve that is optimized for 11-29 and 11-32 cassettes. - Using 3D Embrace technology the inner mechanism embraces more teeth per sprocket thanks to the advanced position of the upper pulley - The 12-tooth pulley wheels allow for the integration of larger cassette range while keeping chain length the same - Upper body adjustments allow you to set the perfect position whether you're riding an 11-29 or 11-32 tooth cassette - An upper body return spring absorbs the energy of any bumps, preserving the hanger, and bringing the derailleur back to position - An aluminum upper body provides high resistance to impacts and greater stiffness - The lower part of the body is made of ultra-light technopolymer, reinforced with long carbon fibers Specifications: - Largest Cog: 32 - Rear Derailleur Mount Type: 10x1 Standard - Chain Wrap Capacity (teeth): 37 - Cage Length: Medium - Rear Der/Shifter Compatibility: Campy Record/Super Record EPS - Drivetrain Speeds: 12 - Weight: 234g

- 2:1 actuation ratio compatible with most Shimano 3x7/8sp drivetrains - Aluminum and steel construction with 11-tooth pulleys barrel adjuster

- Model Number: RD-R3000-GS - Series: SORA - Maximum Sprocket: 34T - Minimum Sprocket: 11T - Maximum Front Difference: 20T - Total Capacity: 43T

Paul Components Melvin Chain Tensioner. Converts frames for single speed use. Long enough for a Dingle-setup, (2 rings, one cog) 20T max. - The Melvin uses two pulleys, just like a rear derailleur, which gives it 20 teeth of chain wrap - Will work with multiple front chain rings while maintaining proper chain tension - The pulleys are made of extruded and machined aluminum and have sealed bearings for durability - Pulleys are 2.25mm thick at the tooth which fits inside most narrow 6 through 9 speed chains, and the pulley cage is wide enough to allow 1/8? single speed chains as well - Long enough for a Dingle-setup, (2 rings, one cog) 20T max - Do not use with a coaster brake or fixed gear - Includes Paul's own Sealed Bearing Pulleys

Shimano Ultegra R8000 Shadow rear derailleur. - Sleek integrated appearance - Low-profile design - Race endurance - Optimized slant angle - Wide compatibility - Short cage covers: 11-25T to 11-30T - Medium cage covers: 11-28T to 11-34T - Model Number: RD-R8000 - Series: Ultegra - Maximum Sprocket: 30T - Minimum Sprocket: 11T - Maximum Front Difference: 16T - Average Weight: 200 grams (short cage type), 210 grams (medium cage type)

SRAM's RED eTap Ceramic Bearing Rear Derailleur Pulleys run on super-smooth and efficient ceramic bearings so your drivetrain pedals with ease. They are also lighter than conventional pulleys. - Compatible with SRAM RED eTap derailleurs

The XX Eagle T-Type AXS™ 12-Speed rear derailleur foundationally changes the relationship between cassette and derailleur. Engineered as integrated, interdependent transmission components, the T-Type derailleur mounts around the wheel axle itself, contacting the cassette directly with a first-of-its-kind Hangerless Interface. Its game-changing Full Mount attachment method creates a far stronger connection and grips both sides of the frame. This XX T-Type rear derailleur features the same intuitive pairing and set-up procedure as Eagle AXS™ derailleurs. - Tucked-in profile houses replaceable skid plates that enhances dependability in high-pressure racing environments - To further its performance, the lower pulley called "Magic Wheel" keeps spinning if an object becomes lodged - Features an overload clutch, accommodates common maintenance and features that real world riders really appreciate - Exceptional shifting performance and unprecedented strength - Aluminum cage - Battery Not Included

Explore the benefits of trekking and urban e-biking with this durable Shimano CUES RD-U8020 Shadow+ rear derailleur's smooth and decisive shifting performance for 2x11-speed systems. A low-profile design and chain stabilization give riders the confidence to keep going. Plus, its premium machine-finished aluminum textures showcase the integration of design and engineering. - Seamless shifting and pedaling performance that's made to last - Chain stabilizer reduces chain drop, slap and noise - Shadow+ low-profile design protects rear derailleur from obstacles in a wide variety of riding scenes - Stylish and polished aluminum finish with machine-cut textures - 11t upper and 13t lower pulley wheels - Compatible with LINKGLIDE AND HG 11-speed chains

Create a more active urban lifestyle with this durable Shimano CUES RD-U8000 Shadow+ rear derailleur's smooth and decisive shifting performance for 1x11-speed systems. Its low-profile design and chain stabilization give riders the confidence to choose rougher routes. Plus, the premium machine-finished aluminum textures showcase the integration of design and engineering. - Seamless shifting and pedaling performance that's made to last - Chain stabilizer reduces chain drop, slap and noise - Shadow+ low-profile design protects rear derailleur from obstacles in a wide variety of riding scenes - Stylish and polished aluminum finish with machine-cut textures - 13t pulley wheels - Compatible with LINKGLIDE AND HG 11-speed chains

- Upper pulley has larger teeth for increased chain control

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.