RUST PROOF MATERIAL: The chain of a single speed bicycle is made of high-grade steel, and the rust proof coating can extend the life of the chain and reduce rust that affects its operation.PERFORMANCE: The chain is stretch resistant and can withstand more wear, which means you can get more bike chain mileage.HOLLOW OUT DESIGN: The chain adopts a hollow out design, which is extremely lightweight and easy to remove internal sludge during operation, making it less likely to get stuck and making cleaning easier.ADAPTATION: Our bicycle chain is compatible with most mountain bikes and road bikes. The CN-HG73 8/9 chain is suitable for speeds of 21/24/27.IDEAL REPLACEMENT TOOL: Chain buckle chain joint, easy to disassemble and install, replacing the old with a new one to make your cycling journey smoother!