All sofa covers are sold piece by piece. This price is for 1 sofa cover (not the whole set).In the size options you can choose the right size, usually a set of sofas requires a combination of multiple sizes! Due to manual measurement, the error of 1-3cm is within the normal range.About chromatic aberration: The product pictures are all taken in kind, as much as possible to be consistent with the real object.Unit: 1 inch = 2.54 cm Pillowcase size 45x45 cm 30x50 cm [without pillow]