Mrs Martin L. Kirchner, Columbus OH

Interesting postage due stamps added.

During World War II, US military personnel stationed overseas, including at Pacific Fleet Post Offices (FPOs), could send letters to the United States at a concessionary airmail rate of 6 cents per half ounce. This rate, established by a law signed on December 13, 1941, applied to personal correspondence from active-duty service members and remained in effect through September 30, 1946.

While the domestic airmail rate for civilians increased from 6 cents to 8 cents per half ounce on March 26, 1944, the military concession rate stayed at 6 cents as a special provision for armed forces personnel. This applied uniformly across theaters, including the Pacific, with no changes specific to FPOs in December 1944 or January 1945. Letters were typically franked with the 6¢ Transport airmail stamp (Scott #C25).

A 1/2 ounce (14 grams) is a pretty light letter. A second sheet of paper, definitely a third, could put it over.