Shop Label
It can be so hard to glean history from a machine. A good shop label can both add to that history and even (when done well) add to the appearance of the machine. A few even have custom key legends!
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Adler Klein Adler No. 2
Thrust
In progress

Adler Mod. 7
Thrust
Unsure
Erika 1
Group

L.C. Smith No. 3
Long Carriage (14")
▶ YouTubeWorks

Merritt
Linear index, steel type
Unsure

Noiseless Portable
Steel Platen, noiseless mechanism
Unsure

Olympia SM4
"Professional Elite" typeface, 11 cpi, #41
Works

Smith Corona Secretarial 250 Office Electric
Cubic typeface, power return and backspace
Works

Stoewer Elite
tipped spools
Unsure

Underwood No. 5
First commercially successful visible typewriter
▶ YouTubeWorks

Underwood Standard Portable "3 Bank"
Very small, early portable
▶ YouTubeWorks