Start of a page on the Eveready A-600 Air Cell battery of the 1930's.
For 'Two Volt' radios - (later there was a version for 'One Volt' radios.)
I'm beginning to think I am being misled by the Eveready Air Cell line drawings I've found to date...

None I have seen show the raised lettering on my case...  Does the museum example have this lettering on the back side?  Maybe the raised lettering is used in the line drawings & publicity photos because the raised lettering does not show as well.

I can see two reasons for getting rid of the raised lettering...

1.  Lower cost of tooling the dies.
2. The paper labels have more 'eye pop' and give the opportunity for maintenance instructions.

Based on what I've seen to date, my example and the museum example must be at least the fourth iteration of the A-600.

The first being released to designers in 1929... (screw caps & thumb nuts)
The second, the first production versions... (screw caps & thumb nuts)
The third, released in early 1933 that significantly reduces the footprint (width) of the battery and increases the height maybe 20%. (screw caps & thumb nuts)) The form factor seen in our units.
Then our units (after Sept 1935 and before late 1937, with Fahnestock Clips and stopper plugs)
Then apparentlly a version with a two pin female connector & stopper plugs.
Then, they went to an A-850 cell??
Above: The hard rubber (?) case just found.  No top.
A neat cut-away in-store advertising model of the A-600 in the collection of the Radio and Technology Museum at Huntington, WV.
Question: Were the versions of this cell that have raised lettering as shown above, shown that way in advertising?
This version has screw caps.
This version has stopper caps.