This is the big one. The master. The large Balance. The OS.
In the early days Sheaffer did themselves, and their advertising department, no favors. None of their pens had model names. They had only cryptic model numbers and size descriptors. This pen is the large Balance model C8T KABAV in the 1937 catalog. Ugh. In the 1938 catalog each pen was given a distinctive name and this would become the Premier. That year the pen imprint also received a price code. This pen would be stamped 1000, for $10. Striped marine green pens were offered from 1937-1941. This pen has no price stamp so is can be guessed that it is most likely from ~1937.
Golden brown Balance were offered beginning only a year earlier than striped marine green. Yet they seem to far outnumber the green pens judging by those found now. I don't know exactly why green pens seem to have been less popular. Vintage pen history is a fascinating mix of information gleaned from reliable records (e.g. catalogs & repair manuals), somewhat less reliable publications (e.g. advertisements) & collector lore. My perception is that striped marine green pens are less common than black and golden brown.
This pen is in excellent condition. The celluloid has no remarkable flaws. The grip section has nice transparency and clarity. I love that the base of the nib is visible along with the ink level. The nib end was likely painted to prevent seeing the nib and feed but I have left it clear. There is no noticeable plating wear or loss. The nib point is fine. Modern pen lovers might consider it more equivalent to a western extra-fine. I have tuned it to be wet and smooth and lovely. It is quite rigid with no line variation.
For reference, the size is almost exactly that of a Montblanc 146.
Length Capped - 141 mm (5.56”) Uncapped - 121 mm (4.8”) Posted - 164 mm (6.45”). Diameter Cap - 14.9 mm (0.59”) Barrel - 13.1 mm (0.52”)