Enhanced Durability and Material Quality: Crafted from premium Aluminum Alloy, this 10T derailleur pulley wheel for its exceptional wear resistance and robustness Optimized Cycling Efficiency with Ceramic Bearings: Featuring advanced ceramic bearings, this pulley wheel minimizes friction and enhances overall cycling efficiency. The design with positive and negative teeth ensures a quiet operation and faster speeds, making it ideal for competitive and recreational cycling. Precision Engineering for : Meticulously engineered, this derailleur pulley wheel boasts superior precision that enhances compatibility and performance with various bike components. Design for Unhindered Performance: This derailleur pulley is not only but also facilitates smooth and flexible rotation. type:10T Support speed: 6-12 Speed Installation aperture: 4/5mm Color: Black Material: Aluminum Alloy Package Contents: 1 x Pulley Wheel 2 x diameter sleeve Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.