The Four-cent Prexie
Multiple rate solo uses
A common solo use for the four-cent Prexie was to pay double the two-cent drop rate in effect for first carrier and then non-carrier post offices from the beginning of the Prexie period until August 1, 1958.
This cover was sent at double the drop rate in Baltimore in 1941. Handstamps on the back say it was "damaged by cancelling machine."
This is part of a wrapper for Our Navy magazine sent in 1943. The second class transient rate was one cent per two ounces from July 1, 1928 until April 1, 1952. The magazine must have weighed between six to eight ounces, or there were several copies in the wrapper. The notation "via air mail" does not make sense in light of the postage paid.
The most likely explanation for the solo four-cent Prexie on this piece is that it was part of a package weighing between three and four ounces sent third class between January 1, 1949 and August 1, 1959. The postage for the first two ounces would have been two cents, then one cent per ounce or fraction after that.
This cover was probably sent fourth class special book rate betwen 1944 and the end of 1948. The rate would break down as three cents for a single book weighing less than or equal to one pound, plus a one-cent war tax surcharge effective from March 26, 1944 through December 31, 1948.