Update Info - 1931 Franklin Duesenberg Lens (updated Info)

A 1930 Franklin uses an 11 1/2 inch lense and they also fit Duesenberg.
A 1931 and 1932 Franklin uses a 12 inch lense and my understanding is they are unique or may also fit a Marmon.
11 1/2 have been reproduced over time
12 inch is a pretty rare lense still
Sorry, no pot of gold, but still work a solid couple hundred dollars if 12"

I believe Model A Duesenberg used Monogram lenses but am unsure of the diameter.

I think Franklin are 12".

Thank you I will look for the marking.

The size of the lens is embossed on the lip under the ring.
Duesenberg used 11 1/2"

I have pair of what are labeled 1931 Franklin Duesenberg Headlight Lenses. I am looking for more information on what they might go on or if the the label is correct. I am cleaning out my fathers storage and we mostly have classic car parts for American cars but I found a set of lenses.
Also what is a good place to list them for sale?

They measure 12"
The Lenses have written on the glass:
MFG. BY Monogram Lens Corp.
Detroit Mich USA 12 IGC
PAT 11-23-20. 7-3-23. 3.29-27.
Twilite Lens
Twilite Headlamp