Compatibility: Converts a multi-speed hub to a single-speed wheel. Compatible with all Shimano and SRAM 7 to 11 speed cassette hubs, for both mountain and road bikes. Note: This product does not convert the hub into a fixed gear; the hub remains a freewheel type.High-quality stainless steel: The sprocket is made of high-resistant stainless steel, with strength and hardness twice that of standard 316 stainless steel, reaching 18 degrees hardness.Chain compatibility: Fits chain widths from 1/2" x 3/32" to 1/2" x 11/128", suitable for 7-speed to 11-speed chains. You can use your original chain. Available in multiple tooth options to achieve the ideal gear ratio.Specifications: Material: Stainless steel Color: Silver Teeth options: 12T, 13T, 14T, 15T, 16T (optional) Processing technology: CNC cutting Package 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 01 cm error due to manual measurement. Verify measurements before purchasing. Due to differences in monitor displays, actual color may vary slightly from the image. Thank you!