We know that regular chain maintenance is key to smooth shifting and long-lasting components, which is why we trust the Park Tool CC-4. 2 Chain Checker to keep us rolling smoothly. Whether we're maintaining our gravel bike, mountain bike, or road bike, this tool takes the guesswork out of determining chain wear, letting us know exactly when it's time for a replacement. Designed with precision laser cuts, the CC-4. 2 measures wear across multiple points on the chain, delivering accurate readings every time. It works with a wide range of chains, from 5-speed to 13-speed setups, including SRAM, Shimano, and Campagnolo, ensuring compatibility no matter what we ride. With clear indications at 0. 5%, 0. 75%, and 1. 0% wear, we can easily follow manufacturer recommendations and avoid damaging more expensive components. Simple, effective, and reliable, the CC-4. 2 is a must-have tool for keeping our drivetrain running smoothly.