describe: * brand new and high quality * Made of high-quality materials, durable and practical Specification: *Compatible with: road bike/bike/mountain bike *Material: Aluminum alloy *Colour: Black *Size: M15(15*28mm)/M18(18*28mm)/M19(19*28mm)/M20(20*28mm) *Weight: about 9g The package includes: 1 x Crank Screw notes: 1. Due to various factors such as monitor brightness, light brightness, etc., the actual color of the product may be slightly different from the picture displayed on the website. 2. Please allow for slight manual measurement deviations i 【High Quality Materials】We use high quality materials to manufacture our products to ensure their quality and durability, and we are committed to providing excellent product quality. 【Sturdy and Practical】Our products have been rigorously tested and verified and have excellent durability and practical functions. No matter when and where you are, our products will consistently provide you with reliable performance and service. 【Easy to Use】Our products are simple in design and intuitive to operate, making them easy to use even for novices. We focus on user experience and hope you can enjoy the use process easily. 【Provide you with help and fun】Our products are designed to provide you with help and fun in your projects, our products will be your right-hand assistant, bringing you a pleasant and satisfying experience. We look forward to your choice and are willing to share this fun with you. 【Excellent After-Sales Service】No matter what problems you encounter, we will solve them for you in time to ensure your satisfaction and shopping experience. If you have any questions about the product, please contact us and we will respond to you within 751 hours.