Extremely rare logic modules like these, made by Radiation, Inc. were part of the ground support computer equipment for Lunar Test Article 8, or LTA-8; the first man-rated Lunar Module in the Apollo Program. It was there in Houston, May 1968, in building 32 at the Manned Space Center (now Johnson Space Center), when NASA astronauts Jim Irwin, John Bull and Gerry Gibbons put the LM through its paces in a vacuum chamber to prove it was finally ready to fly. Pre-dating integrated circuits, these logic modules were very important in their compact, plug design, making servicing super easy compared to the larger, more prominent vacuum tubes of the era. Now you can own a piece of this Apollo History. Each module is unique, and comes with a schematic detailing it’s exact purpose.