As Frank stated the 20-289 was the original, and they are hard to come by these days as RS discontinued them for the USB cable. I sold a pile of the 20-289s and havent seen any in months. Some have used the newer GRE cable with a Serial to USB adapter if you have no USB ports on your computer. Here is a link for the GRE cable which RS carries also in a different color. http://www.greamerica.com/scanner_accessories.html. If you need the 20-289 cable you may put a wanted to buy in that forum and someone may have one to get rid of ....................Hoser