Nexpak Tactical Military Camping Hiking Outdoor Backpack w/MOLLE straps Material: 600 Denier Polyester for daily durable use; PVC lined; hydration pocket accepts 2L Liter bladder, pass-through slot at top for water tube. Excellent storage: 3 zippered front, 1 zippered main, 1 zippered hydration rear pocket: accepts any water bladder, wide padded adjustable shoulder strap with metal accessory hook & large buckle snap Molle Straps, D rings, attachment points: allows excellent attachment of pouches, accessories, caribiners, etc... when needed Large bottle holder with locking drawstring to secure it, accepts bottles up to 4" Diameter Dimensions: 17.5"L x 13"W x 7"D Volume: 900 cu.in.