Classic/Antique Car Repair: IAT Ignition System, charging systems, numbering system

Question
What does the IAT stand for? This would have been used around 1950 on a Desoto.

Answer
The ignition and charging systems in that era Chrysler built cars was manufactured by Auto-Lite. The parts numbering system that Auto-Lite used started with three letters a hyphen or a space and then a number. So, the number stamped on the data plate on a distributor on that car could have been say IAT 4012.