1、OUTDOOR SPORTS: The water backpack is lightweight and practical, suitable for outdoor sports, such as biking, walking, jogging, night running, hiking, marathon and so on. 2、WATERPROOF OXFORD: Running backpack is made of waterproof oxford fabric, tear resistant, lightweight and durable, mesh padded elastic foam provides comfortable back support, increases breathability and helps perspiration. 3、HELMET FIXING MESH: The bottom of the backpack has a mesh pocket design, easy to use storage bag, you can freely store your bike helmet, when not in use, the mesh bag can be retracted 4、SAFE TO USE: Reflective strips ensure safety in any light at night, wear resistant material, outdoor hiking, mountaineering, cycling, the backpack will not be scratched. 5、WIDELY USED: The backpack is suitable for both men and women, and is also a gift to Christmas, Thanksgiving, Father's Day, Mother's Day, birthday gifts and other festivals Item Type: Hydration Backpack Material: Oxford Cloth Size: Approx. 41 x 29 x 10cm / 16.1 x 11.4 x 3.9in 1 x Hydration Backpack