The Brixia light mortar is a 45 mm calibre light mortar mounted on a legged base and designed for operation by two crew. The rear legs are fitted with a pad for the gunner to lay forward on behind the mortar, or sit upon when the situation allowed. A lever allowed for operating the breech and firing the weapon, while ammunition was fed in by the loader. Well trained teams could reach up to 18 rounds per minute, although operational rate of fire was less intense to avoid damage to the firing tube. One interesting feature which set the Brixia mortar apart from comparable WW2 weapons was that it was trigger fired with the help of separate ignition cartridges to be fed into a special magazine, making the weapon more similar to modern cannon-mortars that conventional parabolic grenade launchers of the time.
At tactical level, an infantry battalion had 9 Brixia mortars assigned (rarely, up to 14). The Brixia mortar was assigned to a battalion's mortar platoon, three squads with three mortars each, which were distributed to the companies. The heavier 81mm mortar was assigned to the heavy weapons company.
The Brixia was a complicated weapon and it was costly and lengthy to produce, but, in the hand of skilled operators was superior to other WW2 mortars and could lay down very precise and intense curtains of fire. One lacking feature, however was in the shells, which fragmented poorly and, due to the limited calibre had a very light and low-yield warhead. The weapon, however served on every front where Italian troops were involved (North Africa, Balkans, East Africa, Southern Russia) and was also employed during defence of the homeland against invading allied troops and during clashes between RSI formations and Italian partisans, on both sides, due to many Italian partisans having a former military background it was one of the few support weapons which could be found in the hands of the local Resistance.