The components of mattress support 20 fit into a compact, light-weight packing box that is smaller and weighs less than the packing box containing conventional mattress support 10. Each side rail 11 of conventional mattress support 10 is a single piece of angle iron. Thus, the packing box for conventional bed frames is typically more than seventy-five inches long. In contrast, the packing box containing mattress support 20 in a folded condition has a length that is no longer than thirty-nine inches. The length of the packing box for mattress support 20 that accommodates a twin size mattress is the width of the mattress. However, for versions of mattress support 20 that accommodate larger mattresses, the middle cross bar is made extendable or telescoping so that the mattress support can fit in a packing box whose length is less than the width of the corresponding mattress.
shows the components of mattress support 20 in a folded condition as they would be placed in a packing box. All of the support legs 32-37 are folded in parallel to the cross bars 23-25 in the collapsed state in which mattress support 20 is packed in the packing box. As shown in , third bar 28 and fourth bar 29 fold in adjacent to middle cross bar 25, and first bar 26 and second bar 27 fold in adjacent to third bar 28 and fourth bar 29, respectively. The total width of collapsed mattress support 20 that fits in a packing box is four times the width of a bar 26-29 plus the width of middle cross bar 25. Upper cross bar 23 and lower cross bar 24 can be placed on top of the bars 26-29 in the packing box. For bars 26-29 that are 1.5 inches wide, a packing box that is no wider than seven inches can be used.