China first received a single unit of Soviet Osa-class missile boat in January 1965, and four more in 1966 through 1967 and the last two in 1968.

The range of the boat is more than doubled without significant proportional increase of fuel consumption.

A single unit of Type 021 without the gun is called Hola-class missile boat.

The Hola-class missile boat is slightly larger than the Huangfeng class, with the length increased to more than 42 metres (138 ft).

The mast is redesigned so that it can be folded down when entering the protective cave in the mountains.