One of 5.11's family of Backpacks, the RUSH 12's main compartment is 18"x11"x6.5", for a total capacity of 1330 cubic inches. Also has another 14 compartments to stow and organize all your gear. All the RUSH backpacks are made with tough 1050 water-resistant nylon and feature newly designed fully ergonomic contour yoke system shoulder straps. Heavy-duty YKK zippers and redesigned rain flys keep gear dry and secure. You can even place a hydration reservoir in the internal hydration pockets in these backpacks. Eyewear storage compartment, front organization panel, gadget pockets, all add to the functionality of these backpacks. The detailing is fantastic on these packs.