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Park Tool

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CC-4.2 Chain Checker Tool
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Park Tool
A worn bicycle chain can cause poor shifting and expensive drivetrain damage. The Park Tool CC-4.2 Chain Checker is a drop-in gauge that measures chain wear accurately. It contacts the chain in three places, eliminating guesswork. Compatible with 5 to 13-speed and single-speed chains, it indicates wear at 0.5%, 0.75%, and 1.0%, matching manufacturer replacement recommendations.
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Great replacement cap for my Purist water bottles.
I have really enjoyed using the Range Extender. I appreciate being able to just plug it in when my bike battery is getting low and feel confident I can go another 20 miles!
Satisfied with the watch, quick shipping, pleasant price.
Amazing cycling computer. Was shipped quick and great delivery.