The mark consists of a plus sign: top half green, bottom half blue with a white curved line separating the two colors across the middle of the plus sign and a circular graduated lighter zone approximately one-third of the way from the left of the white line, with a blue shadow effect to the right and bottom of the plus sign. The words DR FUEL CLEAN in all capitals to the right of the plus sign, and the words The Cure for Diesel Engines below, with the letters T, C, D, and E capitalized, all words are in blue except FUEL which is green.