this extension of the base prevents an envelope positioned in the slot from becoming twisted and jammed the corner of the envelope may become awkwardly positioned in the slot and jammed in the aperture or cut out portion 411 that provides access to the robotic arms without this base portion the bottom portion provides for a bottom surface that most of the edge of an envelope may rest against this provides for keeping the envelope straight in that the edge is parallel to the divider as it rests against it fig1 shows a bottom shelf that is configured to receive larger and heavier packages the roller bases 460 and the dividers 450 that include top mounted wheels 490 provide for reduced friction and easier sliding for boxes that include heavier loads by mounting the wheels or rollers 490 on top of dividers 450 as opposed to on their sides a space savings is achieved since only a single wheel is mounted as opposed to having two wheels mounted when in a side configuration fig1 shows a front view for a configuration of dividers 450 and rollers 460 and wheels 490 fig1 shows a shelf removed from the shelving system that shows rollers 460 and 490 fig1 shows a view where some roller bases 460 and wheels 490 have been removed to reveal apertures 910 in which the dividers 450 and the rollers 460 fit the shelf itself may be the same as the other shelves as the apertures may be configured to fit the variety of dividers and rollers fig1 shows the interior of a kiosk system including package slots 1000.