Ultralight and Breathable - This running vest features a water bottle made of premium mesh and nylon material for ultimate comfort, optimized airflow, and to prevent overheating. It weighs only about 130 grams and won't slow you down. Reflective markings and stripes on the front and back increase safety in low visibility conditions. This hydration vest is designed for night running and comes with a 500 ml BPA-free water bottle made of a food-grade soft material (0-40°C). The practical bite valve allows for instant hydration with a simple bite. This running vest is ideal for long-distance running and trail running. Plenty of Storage - This running vest has multiple pockets to organize your marathon and hiking essentials: a large zippered pocket on the back is perfect for storing a light jacket, running cap, or towel. The adjustable front pocket accommodates 250 ml, 350 ml, or 500 ml water bottles. Ergonomically Designed: This hydration vest features a three-point adjustment system (chest strap + waist belt) to ensure a perfect fit and prevent chafing. It remains stable even during fast activities, providing a comfortable and snug fit for easy running. Suitable for Multiple Sports: This unisex running backpack can be used as a running vest, cycling vest, or jogging backpack. Waterproof seams and durable fabric make it ideal for outdoor adventures. This hydration backpack is also a perfect gift for family and friends who love the outdoors. The built-in hydration bladder provides ultimate comfort and absolute freedom of movement.