Compatibility: Converts a multi-speed hub to a single-speed wheel. Designed for all Shimano and SRAM 7 to 11 speed cassette hubs, suitable 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 construction: The sprocket is made from high-resistant stainless steel with strength and hardness twice that of standard 316 stainless steel, achieving a hardness of 18 degrees. Chain compatibility: Fits chain widths from 1/2" x 3/32" to 1/2" x 11/128", compatible with 7-speed to 11-speed chains. Works with your existing chain. Available in multiple tooth options to achieve the ideal gear ratio. Specifications: Material: Stainless steel Color: Silver Tooth count options: 12T, 13T, 14T, 15T, 16T Manufacturing process: 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 note: Allow 0–1 cm variation due to manual measurement. Ensure you are comfortable with this before purchasing. Due to differences in monitor displays, actual color may vary slightly from the image. Thank you!