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The Hafdasa C-4 is an Argentinean sub machine gun that was first created in 1938. Due to it's strong construction, built in dust protector and a wide range of interchangeable stocks the C-4 outclassed similar aged SMGs and is able to match, and in some cases better, the performance of more modern weapons. A machine pistol and full rifle sized variants of the C-4 were also available and are known under the titles C-2 and Z-4 respectively.
The C-4 can be seen twice in the trailer for Call of Duty: From the Cold. The first is in the hands of a soldier seen on the far left of the screen in the tank battle between the Panhard AML and FV-101 Scorpion. and the second is as a sidearm for one of the Argentineans guarding the bunkers.