WEST BIKING YP0719490 Bike Jockey Wheel With Metal Bearings Road Bike Rear Derailleur Jockey Wheel, 11T Black, 11T Red, 11T Colorful, 13T Black, 13T Red, 13T Colorful

1. The chain has good fit and operates more smoothly
2. The deep tooth pattern design effectively reduces chain breakage, provides a crisp shifting mechanism, and ensures a more stable chain engagement
3. The aluminum alloy body with a hollow design is lighter in weight and has better wear resistance
4. The aluminum alloy bicycle drive wheels contain polyurethane, offering lightweight, smooth, low-resistance transmission, stability, wear resistance, and rust resistance, making it suitable for a wide range of applications with a long lifespan
5. Materials: aluminum body + metal polyurethane
6. Size: 11T: about 4.5 x 1 cm; 13T: about 5 x 1 cm