Very small spark plug AC 103

This a pix of an AC 103 spark plug, made by AC Spak Plug, Flint, Michigan. The plug is 2 inches long. Are these even available today and what does it fit? This is an NOS plug.

Thanks

dan

I think it's a 10 mm plug used in many cars of the late 30's and early 40's. I know Packard used them and I think GM. Still available....

Frank

Here is the reply from a Spark Plug collector.

Danny. Your plug is a 10mm size, made 1939-41 for certain model GM and Packard cars. The bad news is that they have no collector value, as the plug companies made millions of them and very few were actually used due to fouling problems. They switched back to14mm as the standard.

Regards

Dan

These fit Cadillacs and LaSalles circa 1940, as well as some Packards and Chevrolets. People referred to these as "peanut plugs". I still use them in my 1940 LaSalle.

While they may not be collectible, I have seen them sell on EBay from time to time. There is a market for them.