A rectangular box includes an internal storage compartment. A removable insert is dimensioned to fit snugly within the internal storage compartment to define a low card storage capacity subcompartment for storing flat rectangular cards with an orientation parallel to the base surface of the box. A foldable divider can be selectively positioned between extended and retracted positions. When displaced into the extended position after removal of the removable insert, the foldable divider subdivides the internal storage compartment into first and second equal sized subcompartments to create a second high card storage capacity where the cards are oriented perpendicular to the base surface of the box.