Collection of pages from K&E catalogs for Polyphase Demonstration Slide Rules
Catalog page from the 1933 Educational Products Catalog
K&E produced large demonstration versions of several of the most popular models. K&E model 101 is a 7 foot version of the 4088. It was intended to hang on a wall or frame for use in classrooms.
Demonstration slide rules were sold early in K&E's history but it is difficult to tell exactly when. It appears that these rules were not shown in the full line catalogs until 1954. Apparently these models were shown in Educational Product Catalogs.
Links to catalog pages for the 101 family of slide rules: