• Easy to use: The bicycle chain gauge is a useful tool for measuring chain wear and determining if it needs replacement. • Normal measurement: The chain will wear out after a long ride. If 0.75 and 1 do not fit into the chain, the chain is normal. • Abnormal measurement: If the chain gauge can be inserted at 0.75, the chain should be replaced. If the chain gauge can be inserted at 1, both the chain and the cassette should be replaced. • Necessary tool: A bicycle chain gauge is essential for any cyclist. A worn chain can damage your bike's sprocket. • Avoid costly repairs by checking your chain regularly with this simple yet important tool. • Compatibility: The chain wear gauge is suitable for all types of bicycle chains, including city, electric, mountain, road, and folding bikes.