Cargo space is maximized with seven compartments: Main compartment with gear straps and two extra mesh pockets; Second compartment contains three map/document pockets, two radio pockets, and pen stalls; Two large pockets on the back; Bottom pouch (12.5" x 6" x 3") with three elastic closure pockets and a zippered pocket; Two side pockets (9" x 5" x 2.5") one on each side; One compartment for hydration systems.