The cap is stamped "WAHL PEN GOLD FILLED MADE IN CANADA". The nib is stamped "WAHL 0 14K 0.585 MADE IN USA". Produced only in the mid 1920s, it is not one of the "usual" pocket-size Wahl pens with nib sizes of 1 and 2 - this is the absolute microdot size, with a "0" nib.
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