Feature: 1. The flywheel undergoes CNC turning processing, resulting in a design that is both lighter and more durable. 2. The internal thread boasts high precision, facilitating smooth rotation and easy maintenance. 3. This freewheel is distinguished by its smooth rotation and minimal noise. 4. The high-precision internal thread ensures a tight connection with the bicycle hub. 5. This freewheel is compatible with various XDR base bike hubs. Specification: The construction, which is both light and stiff, minimizes cassette inertia, leading to quicker acceleration and enhanced chain security. Features: The flywheel undergoes CNC turning processing, resulting in a design that is both lighter and more durable. The internal thread boasts high precision, facilitating smooth rotation and easy maintenance. This freewheel is distinguished by its smooth rotation and minimal noise. The high-precision internal thread ensures a tight connection with the bicycle hub. This freewheel is compatible with various XDR base bike hubs. Specifications: Material: Steel Model: 10-28T/ 10-33T/ 10-36T/ 10-44T (optional) Gear ratio: 10-28T: 10-11-12-13-14-15-16-17-19-21-24-28 10-33T: 10-11-12-13-14-15-17-19-21-24-28-33 10-36T: 10-11-12-13-15-17-19-21-24-28-32-36 10-44T: 10-11-13-15-17-19-21-24-28-32-38-44 Size: 16*15*5cm/ 6.3*5.9*2in Weight: 272g/ 9.6oz Package list: 1 * Cassette Package List: 1 * Cassette