Abstract: Embodiments of a container and method thereof for fitting within a backpack or daypack. The container includes a tubular liner extending between a first end and a second end and defining an axis, the tubular liner including a flexible side wall so that the tubular liner is moveable between a collapsed state and an expanded state. The tubular liner includes multiple partitions defined therein and extends generally orthogonal relative to the axis within the tubular liner. Upon the tubular liner being in the expanded state, the tubular liner includes multiple storage regions defined, at least in part, by the multiple partitions and the flexible side wall. The flexible side wall includes a door flap moveable between an open position and a closed position such that, upon the door flap being in the open position, the door flap facilitates access to the multiple storage regions defined within the tubular liner.