On July 29, 1923, for one-day airmail service on the Vladivostok—Nikolsk-Ussuriysky (now Ussuriysk) and Vladivostok—Spassk-Primorsky (now Spassk-Dalny) routes, additional airmail-rate stamps were issued. On stamps of the Russian Empire’s 17th, 20th, and 21st issues and on stamps of the Omsk government, a lithographed overprint in red ink was applied, consisting of the silhouette of a biplane aircraft and a three-line inscription: "Vladivostok 1923 20 kop." On postal items, these stamps are extremely rare.
Overprint Vladivostok 1923 20 kopecks on 1 Kopeck 1923.
Civil War. Vladivostok.
