Barrett M82 .50cal sniper rifle. Mean 'ol recoil that can break a shoulder. Initial use is for stopping light armor commonly used in ground-to-air(helos!!) or anti-armor roles. Thermal or infra-red scopes allow the user to see the target's body heat through walls and penetrate them or light vehicles. Being in Explosive Ordinance Disposal, he probably sets off marked landmines(Then again, maybe it's the manufacturer logo on his body armor.

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