The Nike hydration belt features two 12oz BPA-free, dishwasher-safe bottles and a convenient zip pocket for stashing small essentials. It is made with 67% polyester and 33% nylon for the body, 100% nylon for the lining, and 79% low-density polyethylene, 13% polypropylene, and 8% thermoplastic elastomer for the bottle. The belt is adjustable and has a buckle.