7075-T6 aircraft-aluminum alloy housing provides for a nearly indestructible aiming system. Two interchangeable dials for the M2 (50 caliber) and M240 (.308/7.62) machine gun allows operator to dial in target distance for specific host weapon. Dry-nitrogen filled to prevent fogging. Integrated detachable rails allow for mounting of laser type sights to the top or side of optic. All materials and coatings are corrosion and chemical resistant.