Bullet point: Excellent waterproofness - Made of high-quality waterproof fabric, the bag is soft and comfortable, and its fabric is clean and flat and has good wear resistance. The rider can safely put clothes, shoes, mobile phones, cameras, kettles into the bicycle bag. The bag is also equipped with a rain cover to keep the items dry at all times. The unique silver rain cover helps for safe night riding. Easy to use - Easy to install, no tools required. This bicycle rear seat bag features two side quality buckles and a strong shoulder strap. Male and female riders can also use the bicycle bag as a handbag or shoulder bag. Double conservation - The four sides of the bicycle trunk are thickened to provide cushioning and reduce vibration when driving on uneven roads. The kettle compartment rope buckle is designed for easy removal and fixing of the kettle. The kettle compartment is equipped with wide-brimmed lights and reflective strips, with wide reflections on both sides of the bag for double safety when riding. Side pocket extension - The bicycle bag supports extended functions on both sides to meet more capacity needs. If not needed, close the zipper. At the top of the bicycle trunk is a mesh bag with a shrink strap that secures the bicycle accessory, such as a mini pump. Note: Please fill the main compartment before using the side pockets. Packaging information - bicycle back pocket with rain cover and shoulder strap, the maximum capacity of 25L; Unstretched size: 35 * 23 * 19cm / 13.8 * 9 * 7.5in, stretch size: 28 * 23 * 34cm / 11 * 9 * 13.4in. Description: Rope seal design - Kettle cabin rope buckle for easy removal and fixing of the kettleSide Pocket extension - Supports expansion on both sides of the bag for easy expansion to meet more capacity needs of users Note: Please fill the main compartment before using the side pockets. Multiple conservation - The kettle compartment is equipped with wide-brimmed lights and reflective strips, with wide reflections on both sides of the bag for double safety when riding * Rain cover provides safer conservation for your trip Main Compartment Expansion - Open the top zipper on the main compartment to expand storage space. If you do not need, turn off the zipper. Elastic band and mesh pocket - The top of the bicycle rear seat bag also has a mesh bag with a shrink strap for securing the bicycle accessory. Product Specifications: Unstretched size: 35 * 23 * 19cm/ 13.8 * 9 * 7.5in Stretch size: 28 * 23 * 34cm /11 * 9 * 13.4in Material: High quality waterproof fabric Capacity: 25L Color: Black / Black & Grey (optional) Packing list: 1 * Bicycle Bag 1 * Rain Cover 1 * Strap