Park Tool CC2 - Chain Checker

The Park Tool CC2 Chain Checker helps alleviate poor shifting and uneven drive train wear. Most manufacturers recommend chain replacement at or before 1% stretch. 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, press the swing arm gauge tight, and then check the gauge window for an accurate reading. Consider that if you replace a chain because of wear other vital drive-chain components may need to be renewed too.