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Allegedly originating from the North Korea as Taedong-B, there are reports suggesting that two boats of this class were delivered to Iran on 22 December 2002.
Design
There is not much known confidently about these vessels. They are estimated to have a standard displacement of 30.4 t (29.9 long tons) and can possibly reach a top speed of 50 knots (93 km/h). From measurements, only length is known to be about 21 m (69 ft). Kajami class can carry two lightweight torpedoes of unknown type. According to Jane's Fighting Ships, the vessel is likely designed for a high-speed approach towards enemy on the surface, and then submerging for almost 3 m (9.8 ft) before using the snort mast for an attack.