a category of products that includes Postal Envelopes, Postal Cards, aerograms, wrappers, and international reply coupons.
All forms of postal envelopes, cards, wrappers etc. which have impressed or imprinted stamps.
Postcards, envelopes, wrappers, etc, on which the postage stamp has been directly printed. Should be kept intact. Where the stamps have been removed they are known as "cut outs".