Features: 1. High-quality materials: The bicycle crankset lock screw is made of wear-resistant 10B21 screw steel, which ensures the hardness and durability of the product and can withstand wear and tear caused by various riding environments. 2. Precise matching: Precisely designed, it is very suitable for the installation and stability of bicycle chains and chains, which helps to improve riding comfort and efficiency. 3. Easy to install: Each package includes a complete set of bicycle toothpicks and roller lock screws for easy and quick installation without additional tools. 4. Wide range of applications: Whether it is mountain bikes, road bikes, folding bikes, BMX bikes or even electric bikes, this chainring screw is an ideal choice. 5. Value for money: Give you the best shopping experience. Whether you are a cycling enthusiast or a bicycle repairman, this toothpick screw will be your ideal choice. Specification: Material: 10B21 screw steel Size: 0.39*5.12in/1.0*13.0cm Color: gold, silver, copper Purpose: To fix the large and small discs on the crankset B width is usually used for mountain bike two-piece chainring locking Type C is usually used to lock a single chainring. If the cap is removed, it can directly lock the smallest chainring on a mountain bike. Package includes: 5pcs Notes: Please allow slight deviation due to manual measurement. Colors may vary slightly for different monitors.