describe: Brand new high quality Introduction: As a tool to protect the bicycle chain, it can protect the chain and frame when the rear wheel is removed for transportation The quick-release design can be quickly installed and removed, which is used to maintain the tension of the chain when cleaning the chain or when transporting a bicycle, and avoid scratches caused by friction between the chain and the body. The drum body is made of nylon with built-in bearings. Does not damage the chain. Note that the roller will follow the movement of the chain! Similar products do not rotate in dry grinding, even if they are made of plastic, they will still damage the chain under high tension! The installation method is similar to the installation of the rear wheel. Adjust the rear dial to Xiaofei so that the guide wheel and the drum are on a horizontal line, and the quick release can be properly locked. Pay attention to the position of the two washers. Size: 7x6.5cm/2.76x2.56'' Notice: 1. Please allow 1-3cm error due to manual measurement. Make sure you don't mind before bidding. 2. Due to the difference of different monitors, the picture may not reflect the actual color of the item. Thanks! 1 x Bike Chain Holder