The M-84AB1 Main Battle Tank (MBT) is a Serbian upgrade of the previous M-84. It is also referred as the M-2001. It was revealed in 2004. The M-84AB1 is similar to the Russian T-90 in terms of capabilities and appearance. It uses a number of Russian components. Some sources suggest that a small number of these tanks are in service with the Serbian Army. It was also proposed for export customers, however eventually it received no production orders from export customers. Notably in 2005 the Serbian M-84AB1 was tested in Kuwait as a part of an international tender. Its main rivals were the Polish PT-91 Twardy and Croatian M-95 Degman. However Kuwait selected the Degman MBT instead.

   This MBT uses Russian-supplied Kontakt-5 explosive reactive armor, Shtora countermeasures system, fire control system, Agava-2 thermal imaging system and many other components.

   The M-84AB1 uses composite armor over the front arc, which consists of steel, titanium, tungsten, aluminum. The tank also has modular Kontakt-5 add-on explosive reactive armor plates. The Kontakt-5 offers protection against modern tandem warheads. The Shtora countermeasures system reduces hit probability of enemy anti-tank guided missiles with semi-automatic guidance. It detects when the tank is illuminated by a laser beam, and automatically triggers smoke grenade dischargers. This MBT is fitted with NBC protection and automatic fire suppression systems. Though some sources claim that in terms of protection the M-84AB1 looses to the Russian T-90.

   The M-84AB1 is fitted with improved 125 mm smoothbore gun and has a carousel-type autoloader. Around 40 rounds of ammunition are carried for the main gun. This tank is compatible with Russian 9K119 Refleks (Western reporting name AT-11 Sniper) anti-tank guided missiles, launched from the tank gun in the same manner as ordinary munitions. These missiles have a range of 4-5 km and can also engage low-flying helicopters. The M-84AB1 has improved targeting systems and is capable of all-weather, day/night firing.

   Secondary armament consists of coaxial 7.62 mm machine gun. There is also a roof-mounted 12.7 mm machine gun.

   This tank has a crew of 3, including commander, gunner and driver.

   This MBT is powered by a turbocharged diesel engine, developing 1 200 hp. The M-84AB1 outperforms the Russian T-90 in terms of speed and mobility. This MBT is fitted with a built-in self-entrenching blade. It can be also fitted with a deep wading kit and is capable of submerged fording. External fuel tanks can be carried for extended range.