G4Free Military Hydration Pack Backpacks with 3L Upgraded Bladder for Hiking, Biking, Running, Walking and Climbing INCOMPARABLE HIGH QUALITY: Water-repellent 600D polester, Self-repairing zippers ,upgraded stitching , Durable hardware,Closed-cell foam back padded hydration pocket MORE STORAGE SPACE : Roomy main storage area is Large enough to carry what you need in the Outdoor activities,Size: 19*12.5*9.5 inches KEEP THINGS ORGANIZED: Two deployment pocket in front of the bag , allows you to store tour gear in an orderly manner, also great for quick access such as guide books and camera GREAT COMPANION FOR OUTDOOR /INDOOER ACTIVITIES :perfect for camping,hiking, vacation, travel, trekking , mountaineering HUMANITY DESIGN AND MORE COMFORTABLE :Adjustable, dual density closed-cell foam shoulder straps can relieve load and feel more comfortable.NOTE:THE 40L BACKPACK WILL NOT COME WITH A BLADDER