My favorite Sheaffer celluloid is Grey Pearl. The depth of the various shades of marbled grey celluloid blocks suspended in clear celluloid gets me staring. Sheaffer made grey pearl pens for only 3 years - 1934-1936. And grey pearl vacuum-fil pens in 1935-6.
This is a Junior size pen but has a larger #3 nib. The clip says Sheaffer'S rather than Sheaffer Jr. That makes this pen match up with model A3W WUKYB in the 1935 and 1936 catalogs. It sold for $2.75 in 1935 but jumped to $3.50 in 1936.
The barrel has good transparency but has turned reddish - collectors call this ambering. The clarity is perfectly sufficient to see the inner works and the ink level. Not such a good thing for productivity while at work as you'll spend your time watching the ink slosh.
The chromium plating on the clip has some pitting and some wear at the ball. Though it is not flaking or peeling so should remain as is with reasonable care. The plating on the cap band is worn.
The original, celluloid covered, carbon steel rod was badly rusted. It has been replace with a new, custom made, black oxide coated, stainless steel rod. The filling system has been restored with modern materials and the pen will fill and work like new for decades.
Sheaffer #3 nibs are bouncy and fun. They should not be pushed like a truly flexible or semi-flexible nib. Even so, they offer enough line variation under normal writing pressure to make you smile with every descender (f, y, g, etc.).
The pen is comparable in dimensions to a Sailor ProGear Slim. The cap posts gently on the barrel end to provide ample length for the largest hands.
Length Capped - 121 mm (4.8”) Uncapped - 107 mm (4.2”) Posted - 147 mm (5l8”). Diameter Cap - 12.2 mm (0.48”) Barrel - 10.6 mm (0.42”)