The 9K33 Osa is a highly mobile, low-altitude, short-range tactical surface-to-air missile system. "9K33" is its GRAU designation. Its NATO reporting name is SA-8 Gecko.

The SA-8 was the first mobile air defence missile system incorporating its own engagement radars on a single vehicle.

All versions of the 9K33 feature all-in-one 9A33transporter erector launcherand radar (TELAR) vehicles which can detect, track and engage aircraft independently or with the aid of regimental surveillanceradars. The 6-wheeled transport vehicles BAZ-5937 are fully amphibious and air transportable. The road range is about 500km.