The Aperture Sight is a precision sight with an open view around it. There is a black cross-hair with a fairly large black dot center. This sight is useful for quick acquisition of targets and keeping scoped in while still being able to monitor your surroundings. It provides the same amount of zoom as iron sights, but with increased peripheral visibility. The aperture sight is useful for medium range sniping and medium to close combat. It is often seen on the STG-44, as the low recoil makes it relatively easy to home in on a target with the aperture sight attachment. The Aperture Sight does not actually lessen recoil, so recoil is a bit more noticeable when using different weapons.

The Aperture Sight is similar to the Red Dot Sight in Call of Duty 4: Modern Warfare. This is only unlocked by completing Marksman II Challenges (75 Kills with weapon) with Rifles and SMGs. The bullet(s) will then shoot at the black dot, as is the case with the red dot of Call of Duty 4: Modern Warfare.