~1940 Black Sheaffer Balance Premier - Vacuum-fil - Medium+
People tend to call this pen an OverSize or OS. It is already quite aptly named the Premier.
It took Sheaffer decades to adopt model names in 1938. Prior to that time it was all base model numbers (2, 3, 5, 7, 8) along with a cryptic set of modifiers to indicate length, color and filling system. I imagine there is a long conversation thread on Fountain Pen Network about how to decode the model numbers. I don't know how and I consider myself rather passionate about the pens. Instead I prefer to call the pens by the names they were given beginning in 1938. It's probably less efficient and harder to remember that something systematic and organized like an engineer would design and love. I just like the names better. Sheaffer also added the price code to the barrel imprint in 1938. The 1000 on the barrel for $10 makes it obvious this pen should be called a Black Premier Vacuum-Fil rather than an earlier 8W WABUB.
This pen is almost collector grade. In fact, only the collectors would consider the following flaws and then only to differentiate the pen from other equally remarkable examples. The barrel has darkened, or ambered, slightly reddish. It remains remarkably transparent with excellent clarity. The barrel has a faint line under the imprint that looks a bit like a scratch. It is evidence of the seam where the sheet of celluloid was welded into a cylinder to make the barrel.
Otherwise, the plating is perfect, the celluloid is perfect, the nib is luscious and the filling system is perfect. I'm confident this pen is from ~1940 when Sheaffer switched back to using celluloid covered steel plunger rods. The rod in this pen is perfect. I've restored it with modern materials and the vacuum is almost strong enough to use as a pogo stick.
Length Capped - 141 mm (5.55”) Uncapped - 121 mm (4.8”) Posted - 160 mm (6.3”). Diameter Cap - 15.1 mm (0.6”) Barrel - 13 mm (0.51”)