I ran into a patch of these today, and I would like assistance in determining which Embossing Index I should apply. (Funny concept with no embossing, huh?) The pieces have a unique profile, with flat domes, flat enough to stand comfortably upside down. Funny digital photo colors aside, the pieces in hand are a kind of dark blue aqua, with heavy mold lines that only go from base to wire groove. All the pieces that I collected seem to have voids in the threadspace, like air was trapped between mandrel and glass during pressing. That's about it for distinguishing characteristics, so I included the "suspect" in a line up of profile standards for comparison. Also included is a look at the inner skirt, showing lack of Brookfield style vent teats.

Does anyone recognize this piece enough to determine if it should be [010] American Product, [030] Pennycuick Style, or something else altogether? I have disregarded Canadian styles, since they were located in mid-state New York, but feel free to correct my assumption if false.

All opinions are greatly appreciated! Thanks!

UPDATED: While not unanimous, the majority of responses received opined that the piece should be given the [030] Pennycuick index.

Many thanks to all that replied!!

BC