 The P 4 torpedo boats consisted of two primary types; the K-123 type with radar, and B-123 type without.The Chinese-built units made the radar standard for all boats, and replaced the original heavy machine guns onboard those former Soviet boats delivered to China with heavy machine guns.The PLAN transferred this class to the naval militia for training purposes, and because these boats are kept and maintained on land due to their small size, they are normally in better condition than larger units that are kept in the reserve and mothballed fleets.