1. This rear derailleur pulley screw for mountain bikes and road bikes is designed specifically for mountain and road bicycles and can fit various bicycle models. It is suitable for all cycling enthusiasts, regardless of gender, including those who prefer a neutral style. 2. The screw is made of metal, offering good robustness and durability. It can withstand the pressure caused by various complex terrains and high - intensity movements during cycling, ensuring stable performance and reducing the likelihood of malfunctions. 3. In terms of specifications, this is a professional titanium alloy pulley screw. This screw precisely matches the rear derailleur pulley of the bicycle, providing stable support and accurate guidance for the transmission system. As a result, gear shifting becomes smoother and more sensitive, effectively enhancing the cycling experience. 4. This product is suitable for sale in multiple regions around the world, including Africa, Europe, South America, Southeast Asia, North America, Northeast Asia, and the Middle East. It is also popular on major downstream platforms such as eBay, Amazon, Wish, AliExpress, independent websites, and LAZADA. Additionally, it comes with an authorized private brand and has reliable quality, making it a good choice for cycling enthusiasts and bicycle merchants.