1930-1970c. collection of covers/postcards with O.A.T. postmarks (Onward Air Transmission - approx. 230 items) including better mixed/combination frankings, different O.A.T. types (large and small formats), countries of origin (Dutch East Indies, Malta, Palestine, Aden, Congo, Trinidad, Ceylon, Burma, Tangier), destinations, registered, censorship etc. In addition some handstamps insufficiently paid for transmission by air mail in 2 Leuchtturm albums
