Waterman's Numbering System

About 1898 Waterman's began using a standard numbering system to describe its pens. This system was modified slightly in 1917 and lasted until the 1930's with exceptions creeping in after 1927. These numbers were stamped on the end of the pen as follows:

Hundreds column

2xx = Sterling Silver barrel covered

3xx = Gold barrel covered

4xx = Sterling Silver barrel & cap

5xx = Solid Gold barrel & cap

6xx = Mother of Pearl (after 1917, 2 gold bands on barrel)

7xx = One 14kt gold band on barrel

8xx = One 14kt gold band on cap

9xx = One 14kt gold band on top of cap

0xxx = gold filled

Tens column

0x = Straight cap

1x = Cone cap

2x = Taper cap

4x = Desk pen (after 1917, safety pen)

5x = Lever filler

6x = Lever filler with slip cap

7x = Eyedropper filler with screw cap

8x = Pump filler

Units column

This indicates the nib size

Additional Markings

1/2 = the pen is thinner

V = the pen is shorter

SF = Self Filler

S = Safety

P = Pump

POC = Pocket

PSF = Pocket Self Filler

X = Larger barrel than standard for that nib size

VP = Vest Pocket

J = Slip cap safety

LEC = Lower End Covered

w.r. = With Ring

Example

A #0552 1/2 is a thin, gold-filled lever-filler with a No. 2 sized nib. A #404 is a silver straight cap with a No. 4 sized nib. A #58 is a lever-filler with a No. 8 sized nib. About 1928, Waterman's began making pens that did not use the above system, such as the #7's, #5's, #94's, #92's, and #32's.

This table comes mainly from the book Fountain Pens and Pencils: The Golden Age of Writing Instruments by Fischler and Schneider.

A more comprehensive guide is available on David Nishimura's site and can be found here: https://www.vintagepens.com/FAQhistory/FAQhistory.htm