A cuirasse breastplate ... for review

[fernando]

This breastplate was discussed here quite a few years ago, so i won't bother you with exhaustive details.
My question now, one that intrigues me since i have acquired it and compared to others out there, it is more on the side of its dimensions. Being undoubtedly a genuine piece, i wonder how such a small (in height) device can fit the chest of an adult, whatever armor version it falls into. Could it be for an infant ? i doubt, as its weight (4 1/2 Kilos) and all consistence has more to do with a grown up.
I have tried to take some (non technical) measurements, hoping that some of you guys are familiar with these things and tell me whether this is a normally sized unit to fit whatever armor type of adult soldier.
All measures were taken straight, except for the chest and waist, that were taken following the curvature
Thank you in advance.

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