Also known as the M1938 or PM-38, the M-43 120mm heavy mortar is a smoothbore mortar with Russian origins. The M-43 is an updated version of its predecessor, the M38, and was widely exported and produced until the final stages of the Cold War. Russia has been the main user of this mortar, although most of its allies also received it. Although it is considered to be an older weapon, the M-43 120mm mortar is still one of the most common heavy mortars used in the world.

The design of the M-43 was based upon the French Brandt MLE 35 mortar with the conventional smoothbore, muzzle-loading capabilities of the M38. Aside from having longer shock absorbers and a few other minor differences, the M43 is very similar to its predecessors. The system is made up of four major parts, including the barrel, base-plate, bipod, and two-wheel carriage. Its fixed spread bipod allows for manual traverse and elevation. For a heavy mortar, the M-43 is surprisingly mobile thanks to its well-designed two-wheel carriage. It is normally towed or transported via a light truck, but it may be hand-drawn by infantrymen over short distances. A crew of six is necessary to operate the weapon. The M-43 120mm heavy mortar provides a large amount of firepower thanks to its ability to fire 12 to 15 rounds per minute at targets as far as 5,700 meters away.