E.A. Laboratories manufactured similar wipers for many years and most of the later replacement types didn't have an internal switch. The ones used by Ford for those early model A cars did. The early EA types have a different cover than most of the aftermarket types.
If you have an October 1928 Coupe, your car was originally equipped with an Owen Dyneto OD-C1B electric wiper. The holes in the windshield frame would not have been evenly spaced as they were for the EA or Heinze wipers.