Compatibility: Converts a multi-speed hub to a single-speed wheel. Works with all Shimano or SRAM 7 to 11 speed cassette-type hub bodies, for both mountain and road bikes. Note: This product does not convert the hub into a fixed-gear (fixie) setup; the hub remains a freewheel type. High-quality stainless steel: The sprocket is made of high-resistant stainless steel, offering strength and hardness twice that of standard 316 stainless steel, with a hardness rating of 18 degrees. Chain compatibility: Designed for chain widths from 1/2" x 3/32" to 1/2" x 11/128", suitable for 7-speed to 11-speed chains. Compatible with your original chain. Available in multiple tooth counts to achieve the ideal gear ratio. Specifications: Material: Stainless steel Color: Silver Teeth options: 12T, 13T, 14T, 15T, 16T (optional) Processing technology: CNC cutting Packing dimensions: Approximately 12 x 8 x 2 cm (4.72 x 3.15 x 0.79 in) Application: Converts multi-speed mountain or road bike hubs to single speed, compatible with 7/8/9/10/11-speed chains Package includes: 1 x Single-Speed Bike Freewheel Note: No retail packaging included. Please allow 0–1 cm error due to manual measurement. Ensure you are comfortable with this before purchasing. Due to differences in monitor displays, the actual color may vary slightly from the image. Thank you!