4054 Polyphase Mannheim

Initially considered a subset of the 4041 family, the 4054 10 inches model - also know as the Favorite- was produced in the United States between 1901 and 1925, and was fabricated with mahogany wood covered with celluloid where the scales were engraved. The cursor was glass with square metallic frame. The models produced during this time had the same scales as the 4041 family, including the inches - centimeters scales. On the back face it had the same table of unit conversions as the 4053, The original cost of this rule ranged during this production period from $4.50 ($159 in 2023 USD) to $6.50 ($159 in 2023 ISD) 

The 4054 was fabricated again from 1944 to 1952, and this new model is considered a subset of the 4053 family, having the same scales set but does not have on its edges the centimeters and inches scales. As the 4053 models fabricated after 1936, it has on the front side the scales A [ B, CI, C ] D, and K, and at the back of the slider the S, L and T scales. On the back face it has the same table of unit conversions as the 4053. More information of this model can be found at the National Museum of American History, and at Clark McCoy, "Collection of Pages from K&E Catalogs for the 4054 Family" The original cost of this rule during this second fabrication period was $ 6.50 ($82 in 2023 USD)

References:

• McCoy, Clark: Keuffel and Esser Catalog Site. K&E Catalogs and Price Lists for Slide Rules.  http://www.mccoys-kecatalogs.com/KEmain.htm 

This website is the most extensive digitla file of Keuffel and Esser product catalogs and price lists (prices  shown here were taken from these lists)  from 1881 until 1972. You can find also user manuals for many slide rule models, as well as other interesting brochures and materials.

• Shawlee, Walter: Keuffel & Esser Co. Slide Rules. https://www.sphere.bc.ca/test/ke-sliderule.html 

This website gives a good overview of models, and other interesting information and links