Tailored Packaging 6x6x4 RSC 32 ECT Shipping Boxes. Tailored Packaging is a brand that you can trust to provide quality packaging materials. The inside dimensions of the box are 6 inches in length x 4 inches in height x 6 inches in width. These boxes are manufactured from 32 ECT single wall, c-flute kraft corrugated material. The package includes 4 bundles of boxes each containing 25 cartons per bundle. Boxes are sent to you flat and unassembled. All corrugated materials are recyclable.