Iran Post issued four stamps and Maxi Cards on November 18, 2001, on Navy Day. Navy Day in Iran is celebrated on November 11 since 1988 to commemorate the major Iranian naval victory over Iraq during the Iran Iraq war.
The stamps were issued in vertical pairs. Scott No. for stamps - 2830 a, b and 2381 a, b.
Tabarzin (P232) - Kaman Class Missile Craft
Alvand (71) - launched in July 25, 1968 as the SAAM (DE 12) the first unit of the Saam Class of which 4 were built. In 1985, after the Islamic Revolution, renamed as ALVAND (71), named after a mountain in Iran.
BH7 Hovercraft - The hovercraft / air-cushion landing craft depict on this stamp is one of six built by the British Hovercraft Corporation, Cowes, U.K., for Iranian Navy, all were commissioned between 1970-1975.
Kilo Class Submarine - It is not sure which submarine is depict on this stamp, but Iran had only three submarines during this stamp issue period, it must be one of the Kilo Class submarines, all built by the United Admiralty Shipyard, St Petersburg, Russia for the Russian Navy. After the disintegration of the Soviet Union in 1991 the three submarines were bought by Iran.
Many thanks to my swap friend, Mr. Hamid Reza Ebrahimi for sending me these valuable Maxi Cards for my collection.
Source: Wikipedia, shipstamps.co.uk