The CC-4.2 is a drop-in style gauge that measures bicycle chain wear.

The laser cut CC-4.2 accurately measures a long section of chain and strategically comes in contact with the chain in three places, quickly and easily taking the guesswork out of knowing when chain replacement is necessary.

A worn chain will cause poor shifting as well as accelerate drivetrain wear. The tool works on any 5 to 13-speed derailleur chain (including SRAM AXS) and is designed to accurately indicate when a chain reaches .5% and .75% wear, the points at which most chain manufacturers suggest replacement.