Bicycle Maintenance Bike Chain Checker Chain Replacement Chain Wear Indicator Gauge Check Ruler

Label:Yes Easy to use Made of stainless steel material Brand new & high quality. Compatible with all chains A worn chain shifts poorly and wears sprockets at an accelerated rate. 0.75% and 1%, the points at which chain experts suggest replacement. Size: approx. 14cm x 4.8cm/ 5.51" x 1.89"(LxW) Package Included: 1pc x bicycle chain checker

Easy to use. With the wheels of the bike on the ground apply a light pressure with the right hand to the pedal to slightly tension the chain. Then apply the tool to the top (the drive side) of the chain. If the tool gauge drops in flat to the chain then the chain is worn past the respective indicator and needs replacing.