5-inch Pocket Mannheim Not Extra Thin
Frederick Post model 1443  [1936-40]

Hemmi model 34P.
Appears in 1936 Catalog and Price Lists through 1940.

Top edge (slanted) : 0-4 inches
Bottom edge: Blank
Back of slide: Blank
Back of rule:  Blank (paper table missing?) 

This page is from the 1936 (18th Edition) Post Catalog 

The catalog describes this rule as "extra thin" but Hemmi made no extra thin model with the scales listed.  The specimen 1443 has the listed scales but is ordinary thickness.  Most probable explantion is that catalog is wrong about thickness.