One bag is enough for your whole necessities needed for a walk, exercise, or day travel. This sling backpack is designed with several pockets of different size to categorize your different stuff. It is made of durable, water repellent polyester with top-quality zippers and durable strap clip. Also with breathable padded shoulder strap and back panel which are extremely comfortable and lightweight and release heat rather than accumulate. Never goes out of fashion and there are multiple colors to choose from.