SCAR-H

The SOF Combat Assault Rifle, FN SCAR, or simply SCAR, is a modular, modern day battle rifle made by FNH. The weapon was first issued to US forces in April of 2009, with a battalion of the US 75th Rangers being the first large unit deployed with the FN SCAR.

Call of Duty: Modern Warfare 2
Not much is known about the FN SCAR, and it is unknown if it will make an appearance in the singleplayer part of the game. It has been identified however, in the CTF multiplayer trailer.