The main differences between the SA-18, the SA-16 and its predecessor Strela-3 (SA-14) included an optional “Identification Friend or Foe”-system to prevent firing on friendly aircraft, an automatic lead and super elevation to simplify shooting and reduce minimum firing range, a slightly larger rocket, reduced drag and better guidance system extend maximum range and improve performance against fast and maneuverable targets, an improved lethality on target achieved by a combination of delayed impact fusing, terminal maneuver to hit the fuselage rather than jet nozzle, an additional charge to set off the remaining rocket fuel (if any) on impact, an improved resistance to infrared countermeasure, and slightly improved seeker sensitivity. Several guerrilla and terrorist organizations are also known to have Iglas.
