Development of the V-75 Dvina air defense missile system, designated SA-2 `Guideline' by NATO, started in 1953 as a medium to high SAM system for use against non-maneuvering targets such as bombers. The system became operational in 1957. The SA-2 is a two-stage missile with a large solid propellant jettisonable tandem booster stage fitted with four large, clipped delta stabilizing fins. Towards the mid-section of the missile are four clipped delta-shaped wings with a second set of small, fixed fins at the nose and a third in-line set of slightly larger moving control fins at the tail. The SA-2A/B/C models can be distinguished by the two sets of four, flush dielectric strip antennas in front and behind the forward fins.