Portable and light: This is a large-capacity seat bag, specially designed for bicycle packaging. It provides a simplified way to transport items without the need for a rear rack. The Velcro straps and buckles are made of lightweight, waterproof and reliable materials, and can be easily installed and removed without tools. Practical and comfortable position: The combination of an updated saddle and compression strap reduces the pendulum effect associated with large rear payloads, provides a comfortable experience for long-distance riding, and reduces flexibility and turbulence. Large capacity: The capacity of the rear bike bag can be adjusted from 3L to 10L. Various items can be stored to facilitate long-distance driving. It can carry up to 8 kg of luggage, but it will not hit the tires. Is a good helper for long-distance travel. Multi-function: 4 waterproof side pockets, convenient for storing small items. The elastic cord on the top of the package is used to store other items.