Interesting WWII cover.
Shoe rationing was announced to the American public on February 7, 1943. It went into effect two days later. This cover is post marked 3 days later from the effective date Feb 9.
Each person received three shoe coupons per year in 1943. This was reduced to two pairs of shoes in March of 1944 because of shortages of leather. Those who needed footwear for work, like mail carriers, and those who were pregnant or needed medical shoes could get additional pairs.

