Red Dot Sight

A Red Dot Sight is a type of reflex sight that specifically uses a red dot as a reticle. it appears in Call of Duty 4: Modern Warfare and Call of Duty: Modern Warfare 2.

Call of Duty 4: Modern Warfare
In Call of Duty 4: Modern Warfare, the Red Dot Sight is available for all weapons except sniper rifles, pistols, and the MP44 assault rifle. When selected as a weapon attachment, the red dot sight replaces the weapon's iron sights. In multiplayer, the Red Dot Sight is obtained by completing the first marksman challenge (killing 25 enemy players in total with the specified weapon) of any Assault Rifle, Submachine Gun, Light Machine Gun or Shotgun. The Red Dot Sight is popular because it allows full peripheral vision and is clearer and easier to use than iron sights. Although the Red Dot Sight does not actually increase the weapon's range or accuracy, it decreases the time needed to aim down sight and decreases the effect of visual recoil.

The scope-style in-game model is based on the Tasco BKRD30, which is mounted on M4A1 Carbines and G36Cs in single-player. The "open" Red Dot Sight, seen on the SOPMOD version of the M4A1, the P90 SD on All Ghillied Up, and the only one in multiplayer, is a Sightmark Sure Shot.

Call of Duty: Modern Warfare 2
In Call of Duty: Modern Warfare 2, the Red Dot Sight has some changes. The new model is a square, being smaller, less obtrusive and allowing a better peripheral view. For the most part, it is similar to the Red Dot Sight in Call of Duty 4. Some weapons now have their own unique Red Dot Sights. The TAR-21 uses the circular MARS Sight, and the F2000 also has its own red dot sight, similar to the optical sight of the TAR-21, but this is incorrect as it should have a 1.6x zoom optical sight. All Red Dot Sights, except for the F2000's and the TAR-21's, are disabled when an EMP is deployed. Getting 60 kills while looking down a red dot sight unlocks the Holographic Sight for primary weapons.