There was a 50¢ per ½ ounce air mail rate to/from the Philippines in effect from April 21, 1937 thru July 3, 1946. Currently, the number of solo uses of the $1 sheet stamp known on cover paying double the ½ ounce airmail rate to the Philippines is: 1. 

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Description: Air mail cover, dated November 24, 1939, with a solo $1 Prexie paying two times the air mail rate from New York, NY to Manila, Philippines.

Owner/Source: Bob Hohertz web site.

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