The first picture is a product picture, the other pictures are sample displays MTB Cassette Mountain Bicycle Freewheel Bicycle Sprocket For Shimano/SRAM Product description: 1. Made of high-strength steel, anti-rust, no deformation, wear resistance and high durability. 2. High-precision threads ensure tight connection and smooth running with the bicycle hub. 3. It can ensure that the chain rotates smoothly without much noise. 4. Provides fast riding speed with less effort. 5. Reliable, suitable for mountain bike flywheels. 7 Speeds 13-28T Product Specification: Name: Bicycle flywheel Material: Stainless steel Weight: 430g Size: 11.5*11.5*c High quality steel, Hollow out design, super light weight. 7 Speed/Freewheel threaded Cog teeth:13-15-17-19-21-24-28T 8 Speed 13-32T Specifications: Color: silver Material: steel and aluminum Number of teeth: 11-13-15-18-21-24-28-32T Speed: 8 speed 6 Speed14-28T Specification: Material: P steel Color: black + brown (as shown in the picture) Style： 6S (14/16/18/21/24/28T) Packing list: 1 * Gear Product List: Bicycle flywheel*1 Note: 1. All pictures are professionally color-coded, but due to the different ambient light and different display device settings, there may be some deviations between the pictures you see and the items themselves. Please understand. 2. The data is measured manually, there may be some deviation, but it does not affect the use.