ACOG

The ACOG (English: Advanced Combat Optical Gunsight) is a series of magnified weapon scopes made by the American company Trijicon. Their scopes commonly offer a magnification of 4x, so anything viewed down the scope will be four times bigger than when viewed normally, and utilise modern materials such as Tritium to improve aiming and target acquisition. The ACOG series of weapon scopes is used by the US Armed Forces, as well as parts of other nations' armies such as the British Armed Forces.

Battlefield 3
In Battlefield 3 the ACOG is seen attached onto an M4 Carbine in all three of the Fault Line Series episodes. It seems to perform similarly to that of Battlefield: Bad Company 2. It is also seen on the M16A4 assault rifle in Operation Métro gameplay. It has been remodeled since the "Fault Line" reveal, as it now has a clearly visible red chevron in the center of the sight. The outside of the scope has also been remodeled, with the fiber optic visible on top, and the rear iron sight removed.