Glyphs of the "#"-like symbol found on common telephone keypads (Unicode character U+2317 .mw-parser-output .smallcaps{font-variant:small-caps}viewdata square), according to the specifications in the standard ITU-T E.161 (05/95) of the International Telecommunication Union. There, the symbol either has to consist of two pairs of parallel lines, either forming a square with overshooting of the ends of 8% to 18% of the total width (here shown: the minimum 8%, intermediate 13%, and the maximum 18%), or forming a lozenge with an interior angle 80° and an overshooting of 18%.
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Karl432