POSTNET — The US Postal Service Code is not classi-fied as a linear symbology because it is based on bar height encoding. It can encode a five-digit (32 bars) ZIP code, a nine digit ZIP + 4 Code (52 bars) and an 11-digit delivery point code (62 bars). The Postnet code can be printed as part of the address block (above the recipient line or below the city, state and ZIP code line) or in the lower right-hand corner of the mail piece. To download the United States Postal Service regulations, go to: http://new .usps.com/cpim/ftp/pubs/pub25.pdf The basic elements are binary digits represented as full bars and half bars. A full bar is the number 1 and half bars represent zero.