SIGNED LONGINES, ANTI MAGNETIQUE, REF. 20175, MOVEMENT NO. 5'724'789, CASE NO. 97, MANUFACTURED IN 1940

According to the Archives of Longines, the present watch was manufactured in 1940 and invoiced to the company's agent Weinstabl in Warsaw, Poland, in the same year. While this watch was destined for Poland, other such Longines aviator's watches with bi-directional revolving bezel and marked "Anti Magnetique" on the dial were used by the Czech military just before the start of World War II.

For further descriptions and illustrations of this type of Longines watch, see Longines Watches by John Goldberger, pp. 120-121 & 124-125 and Military Timepieces - 150 Years Watches and Clocks of German Forces by Konrad Knirim, p. 374-375.