The 9M31 Strela-1 is the baseline missile round for the Soviet 9K31 Strela-1 short-range air-defense system. It was developed under Nudelman OKB-16, produced at the Kovrov Mechanical Plant after the system's 1968 adoption, and paired a 30 kg container-launched airframe with photocontrast homing, a fragmentation warhead, and a roughly 4.2 km baseline engagement envelope.
The baseline 9M31 and improved 9M31M share the Strela-1 launcher family, but western designation references and air-defense references distinguish the original round from the later Strela-1M missile.
| Variant | Configuration | Designation notes |
|---|---|---|
 | Improved missile variant | The 9M31M / Strela-1M is described as the follow-on missile with an improved seeker and the SA-9B or Gaskin Mod 1 designation. Sources: Army Recognition SA-9 Gaskin, Western Designations of Soviet/Russian and Chinese Military Aircraft and Missiles |
The 9M31 was carried in transport-and-launch containers on the 9K31 Strela-1 launcher family.
| Carrier | Carrier type | Carriage evidence |
|---|---|---|
 | Vehicle-mounted short-range SAM system | The 9P31 launcher carried four ready-to-launch missiles on its turret, with sources identifying the baseline 9M31 as the original missile for the system. Sources: ODIN 9K31 Strela-1, Missilery.info Arrow-1 |
Public conflict reporting normally names Strela-1 launchers or air-defense systems rather than individual 9M31 rounds. The missile's strongest sourced context is the launcher relationship, the baseline design, and the split between the original and improved Strela-1 rounds.
| Round | Designation context | Reader note |
|---|---|---|
| 9M31 | Baseline Strela-1; reported SA-9A / Gaskin Mod 0 | Original missile accepted with the 1968 Strela-1 system, using photocontrast homing and a 1 to 4.2 km baseline defeat zone. |
| Improved Strela-1M; reported SA-9B / Gaskin Mod 1 | Follow-on missile identified with an improved seeker and lower minimum engagement boundary while remaining tied to the Strela-1 launcher family. |
Sources: Missilery.info Arrow-1; Army Recognition SA-9 Gaskin; Western Designations of Soviet/Russian and Chinese Military Aircraft and Missiles.
Soviet development of the Strela-1 regimental air-defense system began under an August 1960 decree, with OKB-16 assigned as the main developer for the system and missile.
Sources: Missilery.info Arrow-1, National Defence University of Ukraine Strela-1
The Strela-1 system was adopted in April 1968, and 9M31 missile production was assigned to the Kovrov Mechanical Plant.
Sources: National Defence University of Ukraine Strela-1, Missilery.info Arrow-1
The improved 9M31M / Strela-1M round entered the family after the baseline 9M31, with references distinguishing the later missile by its improved seeker and SA-9B or Gaskin Mod 1 designation.
Sources: Army Recognition SA-9 Gaskin, Western Designations of Soviet/Russian and Chinese Military Aircraft and Missiles
