This sale is for a quantity of one four inch 1980s wafer of Rockwell International CPUs. These are not Chinese made wafers as many other dealers are selling here. I do not buy or sell Chinese wafers. These are genuine vintage American made 5300 series microcontrollers on an uncut silicon wafer exactly as pictured. Comes with shipping case shown. Four inch vintage wafers in good condition are hard to find these days. These are really in exceptional shape and look like they came straight from the cleanroom. I'm selling them at a great price, because I bought them at a great price and I want everyone interested in the technology to be able to have one. These large feature chips would be perfect for the classroom microscope or macrophotography. Rockwell was one of the early silicon valley pioneers of semiconductor manufacture. They developed many key lithographic processes still used in the industry today as well as some of the first single chip microprocessors. Rockwell was also the prime contractor for the Space Shuttle, B1-B bomber, Apollo Command/Service modules, and many other space/defense related projects. This is the real history of the American explosion of electronic technology. See many other rare and beautiful tech collectibles in my ebay store. Thanks for looking!