Hydration Backpack: 2 Liter Water Bladder in Strong, Lightweight Backpack ADJUSTABLE STRAPS: The adjustable straps for your shoulders, chest, and waist are reinforced -- with an easy on-off, double side-buckle design -- to ensure a comfortable fit and eliminates bouncing while you're on-the-go. For comfort and breathability, the shoulder straps are made of a lightweight air-mesh fabric. A special woven air-mesh fabric also covers the comfortable, raised pads which rest against your back. The main compartment is covered with waterproof material. SIZE: Unfilled, the backpack's size is: 17 x 8 x 1 inches. The drinking-tube's length extends to 41 inches. The hydration bladder's capacity is two liters. The shoulder straps' length adjusts from 15 to 31 inches, and their width is 3 inches. The pockets are large enough to hold phones, wallets, cameras, sunblock, umbrellas, sunglasses, clothing, etc. The bladder is designed to help keep the water cool and includes a wide screw cap so you can add ice cubes for a chilled drinking experience. PACKAGE: The hydration bladder is equipped with a "bite valve" for drinking, so there is no need to squeeze it to drink. The tube may be used on left- or right-side of the backpack, so you can access it comfortably with either hand. Thin bungee cords are laced across the back, so larger items -- including jackets, hats, clothing, or even snacks can be easily tucked away. There are two additional D-rings, on each shoulder strap, for clipping on other items. USAGE: Comfortably styled for holiday, camping, fishing, traveling, climbing, hiking, cycling, athletic wheelchairs, etc. The hydration bladder can be inflated, for use as a pillow. Note: For best results, the hydration bladder should only be used for water -- and not wine, milk, or other beverages. Try to avoid contact with harsh chemicals or U.V. light as these elements will damage the bladder.One buckle includes a built-in safety whistle. OUR GUARANTEE: If, for whatever reason, you don't absolutely love your bag, just return it, and we'll refund every penny (or replace it, if there is a problem). NOTE: Please understand that computer displays may differ, so the actual colors of your backpack may vary slightly from that shown. If you have any questions, please feel free to contact us at any time.