From the article:
The SA-9 Gaskin (its NATO designation), called Strela-1M (Arrow 1M) by the Soviets, is a wheeled, amphibious Surface-to-Air Missile (SAM) system based on the same vehicle as the BRDM-2 reconnaissance vehicle. The missile system has both optical and infra-red guidance, and a target ranging radar.
Each vehicle carries four missiles in a ready-to-fire configuration and the crew would then manually load additional missiles once fired. Designed to protect against short-range threats it would often be deployed in conjunction with batteries of ZSU-23-4 self-propelled gun systems making a deadly combination.