Currently, the largest known number of the Canal Zone ½¢ sheet stamp on cover, parcel piece, or tag is: 10.

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Description: Air mail cover from Balboa Heights to Washington, DC containing 10 copies of the ½¢ and one of the 10¢ air mail (Scott C16) on the front paying the 15¢ air mail rate for up to ½ ounce.

Owner/Source: Richard Pederson

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