Park Tool CC-2 Chain Checker

To alleviate poor shifting and uneven drive train wear, manufacturers recommend chain replacement before rear cog replacement. Now you can quickly and accurately determine the wear and stretch of any chain with the Park Tool Chain Checker. Simply insert the Chain Checker’s pins into two links, lightly press the swing arm gauge, and then check the gauge window for an accurate reading

• 5-to-10 speed chains: replace chain at or just before 0.75%
• 11-to-12 speed chains*: replace at or just before 0.5%
• Single-speed chains: replace at or just before 1%
• Check with manufacturer for specific replacement instructions

*Use the CC-4 for SRAM® Flattop™ and SRAM® T-Type 12-speed chains.