Park Tool CC-2 Chain Wear Indicator

A worn bicycle chain can lead to poor shifting and, over time, excessive wear on the derailleur and rear cogs, creating a much more expensive problem. To avoid this, bike component manufacturers recommend replacing the chain at regular wear intervals. With the CC-2 Chain Checker, you can quickly and accurately determine the wear (or "stretch") of nearly any bike chain.

Simply insert the Chain Checker’s pins into two links, lightly press the swing arm gauge, and check the window for an accurate reading. The CC-2 is compatible with most single-speed and derailleur chains*, including Shimano XTR 12-speed chains.