#16 3.0L HYDRATION WATER BLADDER INCLUDED: No more plastic bottles to take up space. Upgraded Quick Release Bladder Bite Valve, just gently biting the valve opens up the flow of water HIGH QUALITY MATERIAL: tough and water resistant high-density 600D polyester fabric, construction rope, high quality buckle 2 FRONT POCKETS and 1 MAIN POCKETS: Use the front pockets to carry your wallet, keys, phone, towel, small tools or other items; the main pocket can organize your other large stuff well MULTIPURPOSE: Perfect for hiking, running, cycling, walking or taking with you for a day LARGE CAPACITY: The whole pack size: L 8.26 * H 19.68 * W 4.72 IN, Volume:12L; Bladder 3L. Enough space to hold your necessities for travelling. NOTE：It will be easier to suck the water out if you could suck the air out first when receiving the bladder.