Notes: "The Aristo 661 Naviat appears to be for boats, with the “wind slide” going all the way up to 30 knots, and the calculator side having no air data calculations at all (density altitude, true airspeed, etc.). It appears to be entirely for time-speed-distance problems. Aristo seems to have been the major manufacturer of flight computers in Germany (like Pooleys in the UK or Jeppesen in the USA), making a wide variety of them."
