The easy-to-use athletic reservoir fits right into your hydration pack. It holds 100 ounces - or 3 liters - of fluid and can be used as a replacement reservoir or your very first one. Markings on the front let you to track your fluid intake, and you can mix your favorite drink or electrolytes. This athletic reservoir is BPA-free, odor-free and taste-free, and the easy flow bite valve makes hydrating simple. Keep your hands free and your hydration up when you use the 100 oz hydration reservoir. Slide lock opening with large opening accommodates ice cubes and easy cleaning after use BPA-free. Utilizes radio frequency welded seam technology on seams and exit port to ensure a strong leak-proof bond angled easy flow bite valve provides a constant flow-rate TPU tubing is odor free and taste free, volume markings on the front for making it easy to mix electrolytes or your favorite drink 100 oz (3.0 L) capacity