A signature may contain one or more images but they must fit within a  box with maximum dimensions of 400 x 75 pixels (width x height) and  with a maximum (combined) file size of 20k. Images containing mostly  very large words or animated .gifs will not be permitted. You may also  add 1 consecutive lines of normal or smaller text directly above or  underneath the image with no spaces inbetween image and text. If no  images are used then up to 4 consecutive lines of normal or smaller text  is permitted. Do not pad out your text lines with blanks lines. A line  of text is defined as having a maximum length of 400 pixels.