1. This washer is suitable for mountain bikes, road bikes, balance bikes, and scooters. It is made of aluminum alloy and comes in two sizes: 5mm and 10mm. A set contains a total of 6 pieces, including 2 washers of 5mm and 4 washers of 10mm. 2. The aluminum alloy material gives the washer good performance. It is sturdy and durable, able to withstand a certain amount of pressure and friction during vehicle use, providing reliable support for the stable operation of the vehicle. 3. It is compatible with various types of bicycles. Whether it's the complex road conditions of mountain bikes, the fast - paced riding of road bikes, the flexible control of balance bikes, or the basic practice of scooters, it can play its due role. 4. It can effectively meet the needs for washers in different riding scenarios, providing precise support and stable connection for bicycle components. It is a practical accessory for improving the performance and stability of bicycles.