Northstar Tactical Expandable Hydration Rucksack Military Pack Measures 17 - t x 7 w x 4.5 D - inches fully extended made with rugged Tuff Cloth for long term use and reliability Lined Hydration storage compartment accommodates 3 Liter bladders (Bladders Sold Separately) Other features include a large zippered compartment for packing additional gear, provisions, or extra water bladder, plus a smaller outside pocket w/ 2) inside 3 x 4- inch vented storage pockets, perfect for cell phones, flashlight or lighter Adjustable padded shoulder harness and waist belt with quick release buckles and cool mesh backing for a comfortable hiking experience M.O.L.L.E compatible, multi-use lightweight load-bearing tactical equipment