Park Tool CC-3.2, Chain wear indicator

Keep your bike running smoothly by regularly checking and replacing your chain. The Park Tool CC-3.2 accurately shows when your chain is 0.5% or 0.75% worn, indicating it's time for a new one. Works on most 5-12 speed chains.

• Up to 10-speed chains: replace chain at or just before 0.75%
• 11 and 12-speed chains: replace at or just before 0.5%
  

Not necessarily intended for use with SRAM® Flattop™ or SRAM® T-Type 12-speed chains