1. This is a hydration pack designed specifically for outdoor sports, suitable for scenarios such as cycling and running. 2. The backpack is made of canvas material, which is sturdy and durable. It can withstand various frictions and collisions during outdoor sports, providing reliable companionship for your trips. 3. It has a large capacity of 2 liters, sufficient to meet your drinking water needs during long - term outdoor sports, allowing you to replenish water at any time during the exercise and stay energetic. 4. In terms of design, this backpack features a double - shoulder strap design, which is comfortable to carry. It can effectively distribute the weight and reduce the pressure on the shoulders, making you feel more relaxed during sports. Additionally, the overall design is simple and elegant, with great aesthetic appeal. It is not only practical but also can be a fashionable accessory for your outdoor sports. 5. This backpack is designed in a one - size - fits - most style, suitable for users of different body types and highly versatile. Whether you are a professional outdoor sports enthusiast or a novice who exercises occasionally, you can easily use this hydration pack. Although it is not equipped with a rain cover, with its excellent design and material, it can still be a good partner for your outdoor sports. 6. Choose this hydration pack and start a comfortable and fashionable outdoor sports journey.