Features: This product is crafted of high grade materials, small and exquisites designs doesnot take up space, screws to fix the installation of fast, aluminium alloy bells cover to make the bells more penetrating sound louder. The bells can be installed inside the location hiddeness installation is not easy to find, the location signal is not interfered with, at anytimes to find the bike; The product is suitable for 22.5-27mm handlebar tube diameter, you need to measure the handlebar tube diameter before purchase. Compacts bells with crisp and loud sound, compared with the traditional bells, it have more convenient operations. Suitable for mountain bikes, roads bike, city bikes and children bicycles etc. Specifications: Component:ABS Size:As Picture Shown Color:Black Package Includes: 1pcs Bike Holder with Bells note: ①.Please allow 1-2cm errors due to manual measurement, make sure that you donot mind befores you order. ②.Due to the differences between different monitors, the picture may not reflect the actual coloring of the item. Thanks for your understandings.