Description: 【Rear Derailleur Protection】Installed to the rear wheel, Bike Light Holder bracket can protect the rear derailleur when the bicycle accidentally rolls over. 【Bike Light Mount Adapter】After installing the rear wheel, you can install the warning light on, which will provide additional safety when riding at night. 【Multipurpose】Installed on the front wheel, night driving lights can be installed on it to up the space on the handlebars. At the same time, the height of the lights can be lowered to avoid directly shining into the eyes of passer by. 【Quality Material】Quick Release Light Holder is made of high strength aluminum alloy material, solid and durable, higher oxidation resistance, higher hardness. 【Antiskid design】: Special antiskid treatment is applied to the surface to prevent slipping and loosening. It is suitable for use with M5 quick release levers. Specification: Material: Aluminum Alloy Length: 6cm/2.36inch Outer Diameter: 22mm/0.87inch, M5 Thread Package Includes: 1 Quick Release Bike Hub Mount Light Holder Note: Please allow slightly errors due to manual measurement and different monitors.