The Y-shaped compression strap that Maxpedition is so famous for contributes to the bag's form and structural integrity. Exterior PALS webbing for adding other Maxpedition pouches and accessories, using #9903 3" TACTIE and #9905 5" TACTIE ATTACHMENT STRAPS. Main compartment approx. 9.5"(L) x 18"(H) x 5"(W);Additional storage-13"(L) x 14.5"(H) zippered hydration compartment accommodates up to 100oz/3L hydration reservoir with bi-directional tube port (sold separately) Straps-2.25" adjustable padded, breathable backpack straps with 14 channels of PALS webbing and 2 D-Rings attachment points;Removable sternum strap made from 1" webbing with 1" quick release buckle Made with high quality nylon stitching, self-repairing YKK zippers and a durable water-resistant exterior; Maxpedition Backpacks have multiple compartments and pockets