Rare? Gershman height gage, Pat. Jan. 25, 1966
I did a patent search today on Taper Micrometer Corporation mikes, invented by George L. Gershman. They are not antique, but are very rare and collectible.
I found one of Gershman's patents was for a height gage. I suspect it never got produced, which would make it rare indeed. He probably made a prototype, which was probably lost. I thought you guys that pay the nutty prices (I pay nutty prices too, but for other stuff) for rare antique height gages might not even know about the Gershman design. The patent (3231228) was issued Jan. 25, 1966.