[Design]: Exercise Bike Resistance Knob for most bikes and Exercise Bike. [Material]: Made of plastic and metal material, durable and functional. [Feature]: The knob small and portable, will not scratch your hands due to winding. [Easy to install]: The knob is easy to use and quick to install, it will not take up too much time for you, and it is very convenient. [Applications]: The Bike Knob Exercise Bike Accessory is widely suitable for strength and fitness equipment, exercise bikes, etc. Type:10 Gears/8 Gears Colour:Black Material:Plastic Package Contents: 1 * Exercise Bike Resistance Knob Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. Note: 1. Please allow 1-3 mm error due to manual measurement and 1-3g weight error make sure you don't mind before ordering. 2. Due to the lighting of the photos and the difference of monitors, the pictures may not reflect the actual color of the real item. Please make sure you don't mind before ordering, thank you! About Shipping: 1.please pay attention to your delivery address such as: name, street, house number, doorbell/email without name, etc. is correct, or the order will not be delivered correctly. 2.All items will be shipped within 3 business days after the payment is received. Most times you will receive them within 8-12 days then. The specific delivery time is depend on circumstances. 3.During the shopping process, if you have any questions, please feel free to consult us, we will reply you within 24 hours Hope you have a pleasant shopping experience!