The US numbering system did not have A, B, or C models. For lever fillers, they used 4 for standard length, 5 for vest pocket length, and 7 for slender vest pocket length as the first number in a two digit code. The second number is the nib size. (Eye Droppers started with a 1).
They stuck strictly to numbers, there was no SF designation on US pens. 3 digit codes were only for overlays and decorative cap bands.
Eventually they added letters to differentiate black, red, and mottled hard rubber.
The American Mabie Todds stuck pretty closely to this numbering scheme (with exceptions) right up to the end in the late 30s. The British and US numbering schemes have very little in common. Id suggest not looking at an American Mabie Todd pen and trying to figure out a British number for it.
Edited by MarcShiman, 27 September 2017 - 05:53.
HEISERMAN PEN SWAP
Dec 9, 2017 - 10-3pm
Brookville Academy, Brookeville, MD
Free admission, no dealer tables. Bring your pens and trade