A transferable insert for organizing the interior of a bag includes a pair of side walls, a pair of end walls and a bottom wall substantially continuously interconnected so as to define an interior storage compartment, a first and second expansion panel each being operatively moveable between a collapsed position and an expanded position to conform to the width of the interior of the bag, a first and second expansion fastener structured and disposed for holding the respective first and second expansion panels stowed in the collapsed position, and a plurality of pouches within the interior storage compartment for holding and positioning a plurality of objects therein in an organized arrangement. A releasable fastener on each of the pair of end walls may be used for releasably holding one of the pair of end walls in a gusseted position.