PARK TOOL CC-4.2 CHAIN CHECKER

The Park Tool CC-4.2 Chain Checker is a precision laser-cut gauge designed to measure chain wear before it damages your drivetrain. This drop-in style tool contacts the chain at three strategic points, providing accurate wear readings across 0.5%, 0.75%, and 1.0% thresholds—the critical points for chain replacement. Compatible with 5 to 13-speed derailleur chains, including SRAM T-Type, SRAM Flattop, Shimano XTR 12-speed, Campagnolo Ekar 13-speed, and single-speed chains, it eliminates guesswork and helps prevent costly component wear. Regular chain maintenance with this tool extends drivetrain lifespan and maintains optimal shifting performance.