This letter scale made of magnetic steel is named SAV-A-STAMP. It has a range of 8 ounces. The postal rates are engraved at the frontal side of the scale. The back surface is kept totally bare. The scale has the maker's name: Thorne-Foster Inc., N.Y.C. Also mentioned is pat. pend. to indicate a patent is applied for. The postal rate of 3c for a letter was valid in the period 1932-1958, the 6c for airmail was valid from 1934 till 1944 but also from 1949 till 1955. A long side edge could be used as a 4 inch ruler. The letter scale looks to be based on the American patent with number 2,060,064. It was granted on November 10, 1936 to John C. Fryer. The application was already made on April 14 1933. Probably this scale dates from the period 1933-1936. The text of the patent mentions a third function of the design: a paper weight. The 7 figures of the patent show scales that differ on many details: other letter clips, other scale ranges, differently shaped indicators, and other shapes of holders. The SAV-A-STAMP of A. Browne Co. is of a more recent date and shows the above mentioned patent number. Below some more pictures of this letter scale.
Thorne-Foster letter scale
