Ergonomic and breathable design for a long-lasting dry back: • The vest-like structure follows the contours of the back and uses breathable mesh material to promote air circulation and prevent heat build-up. This keeps the back cool and comfortable, even during prolonged exertion. Ultralight with a weight of only 142 grams, suitable for a high-capacity hydration bladder: • Weighing only 142 grams, the main compartment accommodates a 1.5-liter hydration bladder, and each of the two hip pockets holds a 250 ml PET water bottle. The lightweight design significantly reduces the burden during exercise. Multiple pockets for secure storage and easy access to items: • Two large and two small front pockets offer organized storage for small items such as phones, keys, energy gels, and tissues. Reflective stripes increase safety when exercising in the dark, and clips on the shoulder straps prevent the strap from swinging. Adjustable shoulder straps and waist belt for a unisex fit: • Both the shoulder straps and the waist belt are flexibly adjustable for different body types, ensuring a stable and snug fit during running and cycling and reducing swaying and bouncing. Suitable for various sports scenarios, low air resistance and high stability: • Specially designed for outdoor sports such as cycling, running, and hiking. The vest fits snugly against the back, has low air resistance, and does not sway, making it suitable for various intense sports scenarios such as road cycling, trail running, and mountaineering. Product Specifications Product Name: Sports Hydration Vest/Backpack Material: High-quality nylon + breathable mesh material Weight: Approx. 142 g (excluding hydration bladder/water bottle) Hydration Bladder Capacity: Suitable for 1.5-liter hydration bladders (hydration bladder sold separately) Water Bottle Compatibility: Each side compartment holds a 250 ml PET bottle Storage Compartments: 2 large front pockets + 2 small front pockets Safety Design: Reflective stripes, adjustable shoulder straps and hip belt, shoulder strap clips Suitable for: Cycling, running, hiking, mountaineering, skiing, training Suitable for: Unisex (adjustable straps for different body shapes) Package Contents: Sports Vest/Backpack × 1 Color: Black