| Starting in 1988, tanks M1A1 received the | | | | the MCD is box-shaped and fixed in place as |
| packages improved of armor which incorporated | | | | opposed to cylindrical and rotating like the |
| the mesh out of uranium exhausted in their | | | | CITV. The main armament of the original model |
| armor in front of the turret and the hull. | | | | M1 was the M68A1 105 mm rifled tank gun |
| The armor reinforced this manner resistance | | | | firing a variety of HEAT, high explosive, |
| appreciably increased of offers towards all | | | | white phosphorus (smoke), and a highly |
| the types of the armaments anti-tank device, | | | | efficient and lethal anti-personnel (multiple |
| but at the expense adding the considerable | | | | flechette) round. This gun is a license-built |
| weight to the tank. First tanks M1A1 to | | | | version of the British Royal Ordnance L7 gun. |
| receive this leveling were tanks posted in | | | | |
| Germany, since they were the first line of | | | | While being a reliable weapon, the 105 mm was |
| defense against the Soviet Union. In addition | | | | becoming obsolete in the face of advances in |
| to the Abrams' advanced armor, some Abrams, | | | | armor technology, which meant that a better |
| most notably M1A1s of the US Marine Corps, | | | | tank gun was needed for the M1. The main |
| are equipped with a Missile Countermeasure | | | | armament of the M1A1 and M1A2 is the M256 120 |
| Device that can detect and jam the guidance | | | | mm smoothbore gun, designed by Rheinmetall AG |
| systems of laser-guided anti-tank guided | | | | of Germany. The M256 is a variant of the |
| missiles (ATGM). | | | | Rheinmetall 120 mm L/44 gun manufactured |
| | | | under license in the United States by General |
| This device is mounted on the turret roof in | | | | Dynamics Land Systems Division in their plant |
| front of the Loader's hatch, and can lead | | | | in Lima, Ohio. It is the same armament |
| some people to mistake Abrams fitted with | | | | carried by the German Leopard 2 tank up to |
| these devices for the M1A2 version, since the | | | | the version A5 until replaced by the longer L |
| Commander's Independent Thermal Viewer on the | | | | 55 gun in version A6. |
| latter is mounted in the same place, though | | | | |