Durable: The bicycle chain wear indicator is made of high quality carbon steel with nickel-plated surface, which has good wear resistance and is not easy to wear, sturdy and durable for long time use. Suitable size: the length of the chain wear indicator is approx. 14cm/5.51inch, flat design, suitable size, lightweight and portable, easy to carry and store, and takes up less space Easy to use: just insert the wear checker from the chain in the bicycle chain, if the end (.75) can not be inserted, the chain wear rate is normal, no need to replace, if the end (.75) can be inserted. but can not be inserted, it is recommended to replace with a new chain, if it can be inserted at the end (1.0) the chain should be replaced as soon as possible Important bicycle repair tool: the chain gauge measuring ruler can be used as a basic and important tool in daily life to help you measure the wear rate of the chain to determine whether it needs to be replaced with a new chain, which can effectively prevent the accelerated wear of the chain. flywheel and disc Wide range of applications: The bicycle chain measuring tool can be applied to most kinds of bicycles, a good helper in daily life, make your bicycle work normally and bring more convenience to most people.