The example of Espero’s works I’ve have a chance to handle is, I suspect, fairly representative of what they got up to, but it also calls for a certain amount of guessing. Leaving that aside for the moment, what one has is a pen slightly on the large side of average size, of decent fitting but with very dubious plating on the hardware. The clip is interesting, as it is mounted on a very flexible bit of steel in such a way that it can be opened like a clothes-pin, similar to earlier Conklins and the later Sheaffer Stylist.
Performance is a vexed question. The one I held was rather brilliant, with a smooth, soft, flexible point. However, it was also a British-made point, which probably got installed well after production. Other examples I’ve seen in pictures have extremely cheap low-end “spoon” points, where the role of tipping is taken by a dent in the end of the steel tines… but those are US-made points, and may not represent original parts either. It may be that either or both are actually original, representing different times of production; I’ve no information to establish the truth.
Also, the innards of the exemplar here were simply absent, so I cannot really comment on their powers. Sacs are sacs, of course, and in pictures the pressure bars of others seem serviceable enough– no more or less flimsy than what Parker was offering in the 1940s. Button-fillers are hard to mess up on.
One note to anyone who might be working on a similar pen; the section is hard rubber rather than celluloid, so don’t leave it soak if you like the colour it currently has.
Production Run: c. 1940 – c. 1950. As I have almost no grip on the functional lifetime of the maker, I offer this decade as a rank speculation more than as an data point.
Cost When New: I hope very little.
Size: 14.0 cm long capped, 16.3 cm posted, 11.6 cm uncapped.
Point: Probably plated steel originally.
Filler: Button filler , capacity approx. 0.8 ml
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