Cubertas-CC Cubiertas as the following items are known as were used on the backs of insured letters. The were gummed on the back and applied as a large stamp to seal and secure the contents of the envelope. The were addressed and either cancelled by hand or with the regular postal cancellation. The date was shown by the printing of either the first two or three figures of the year usually shown at the right center. 这是原文(未校验拼写错误)。