Model 20e is very similar to the model 12e or 16e (see description of Madas 12e). The keyboard has a capacity of 10 digits, but the “Counting Register” has 10 digits and the “Product Register” has a 20-digit capacity. Notice that there is only one key for Additions or Subtractions. A small lever allows to choose between these operations.
Like many other “Models 20”, this model makes use of a split-lever for partial clearing of “Register I”. This is a small black lever situated centrally on the carriage above the direct access keys of “Register I”. When the lever is horizontal, normal clearing of the entire 20 digits of the “Product Register” is operative. When, however, the lever is set in a vertical position, dials 1 to 7 only may be cleared.