Rothco's 2.5 Liter Hydration System features Hook N' Loop Closed Bladder Compartment, Full Length Zippered Main Compartment, Mesh Accessory Pouch, PVC Coated Zippered Carry Pouch, Spring Hinged Bite Valve, Detachable Hose, Easy Fill Bladder, 600 Denier Polyester Construction, Nylon Lining, Padded Mesh Back, Vinyl-Lined Padded Adjustable Shoulder Straps, Waist Straps, Top Carry Handle.