It means that each side of a pillow cover may be cut from different parts of the fabric pattern, so that the portion of the pattern shown will not be identical. Typically home decor fabrics are 54 inches wide and has a vertical pattern repeat that is differs from pattern to pattern.Generally speaking, on most prints (including pictorial, floral, paisley, ikat, striped, abstract or designs with wavy elements), each pillow cover will show a unique section of the fabric. On geometric or medallion prints, best efforts are made to center the pattern symmetrically along a vertical axis, but in multicolor designs multiple symmetrically-cut covers may still show different color sequencing. If you are buying more than one cover and absolutely require both an identical pattern arrangement and identical color sequence on each cover, please inquire prior to purchase to make sure the fabric inventory can accommodate. Identical matching in both cut and color requires more fabric to accomplish and additional charge may. The larger the fabric repeat, the more material is required to cherry pick a repeatable cut, and therefore the higher the cost. For example, 2 covers for a 16 inch insert can normally be cut from 1 yard of fabric. However, if a motif repeats itself only once every 30 inches, to obtain identical cuts on both (meaning 4 identical cuts for the front and backs), you will need 4 x 30 inches = 120 inches or 3 1/3 yards.