Maker: Alster
This pen suggests to me a low-end pen made in Europe, or at least for the European market. The filler and overall shape of the pen suggests the earliest Pelikan pens, while the glass point was a means adopted by various makers of cheap pens from the 1930s to the 1950s to avoid the skilled labour costs associated with metal points. Glass points could, after all, be run out of molds by only slightly trained workers.
Production run: I suspect the 1930s, but have no evidence to support that beyond a cork seal on the piston.
Size: 12.6 cm long capped, 16.8 cm posted, 11.7 cm uncapped.
Point: Glass.
Body: Celluloid.
Filler: Piston, capacity approx. 0.8ml
Alster pen, with its extremely stereotype German clip
The cap impression is what I'm basing the name upon; like the earliest Pelikans, it's a lot shorter capped than posted
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