SAM sites are seen in Payback, where they try to shoot down the Hind captured by Woods and Mason.
Call of Duty: Black Ops II
David Mason uses a SAM in "Cordis Die" to take down incoming drones that threaten the President; it is also seen in "Judgment Day". It is a controllable anti-air ground-to-air missile launcher with an unlimited lock-on limit.
Gallery
Using SAM Turret in 1st Person.
Interface.
Trivia
Call of Duty: Modern Warfare 2
The SAM emplacement used by Ultranationalists and Shadow Company appear to be utilising AIM-120 AMRAAMs, an Air-to-Air Missile, not a Surface-to-Air type.