4-inch Vest Pocket Slide Rule with Magnifying Lens
Frederick Post model 1441 [1949-71]
Teledyne-Post model 44DA-410 [1972+]
Hughes-Owens models 1760 (early),  341 3405 (late)
Hemmi model 32.  (Hemmi model 32R from about WWII to 1950.  The "R" was added to the Hemmi model number when the CI scale was added in the early 1940s.  The "R" was dropped about 1950.  The Post model number was always 1441--except 1447M for a short period just after Post started selling Hemmi rules in 1931. )

1949 Frederick Post General Catalog,  Pages 70-71

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