Hello Reinier and Ben,
in my collection I have no Sphygmomanometer Aneroid(item 3737000),but on the Index of Med 3 from Medical supply Catalog
March 1,1944,this item is named (TYCOS),no other manufacturer.
Below,my own Sphygmomanometer Mercurial(item 3738000) complete with mercury inside !!!
Made by W A Baum Co. Inc. New York.Patent number 1 821902,this patent has been registered between 1931-1932 years.
With my best regards.