Coaxial machine gun

An coaxial mount is when the gun is mounted besidet the main armament. Coaxial weapons are usually aimed by use of the main gun control. It is usually used to engage infantry or other "soft" targets when the main gun collateral damage would be excessive, or to conserve main gun ammunition.

Battlefield 2
Both the M240 and PKM appears as an coaxial variation, they can be used by M1A2 Abrams T-90 LAV-25