The Ultra PRO Citadel is a heavy duty backpack with compartments large enough for several deck boxes, PRO Binders, and even an Ultra PRO Cube!  It also comes with a weather-resistant, removable cover flap (accessories not included).
Over 1 cubic foot of space in main compartment, large enough to carry an Ultra PRO Cube.
Security compartment under the straps for valuables.
Easy access compartment for small personal items.