The M4A3 CCO is a modified version of the M4A1 with a flashlight and CCO (Close Combat Optic) red dot sight attached. The sight provides no magnification, but does help to reduce the recoil on the weapon. The desert camouflage pattern painted on it is slightly less visible in the brush, making it a desirable assault rifle for those wearing a Ghillie Suit or Camo Clothing.
The attached flashlight, ability to use silenced rounds, and slightly lower recoil make this the best medium range weapon in the game for operating in the dark.
- Although not a silenced weapon, it can use 30Rnd. STANAG SD ammo which produces a silenced audible range effect for zombies while players hear an unsilenced report, however when using 30Rnd. STANAG SD ammo the red dot is not where your bullet will hit, the actual hit zone is about 3/4 of the distance from the top of the iron sight pin to the red dot ABOVE the dot
- The flashlight attached to the weapon has the same drawbacks as the standard Flashlight and so should be used with care.
- Depending on the HDR setting of another player or whether they are using NV Goggles, shining the flashlight directly at them may be blinding while also lighting up the target for improved aim with the rifle.