The FMU will provide organic fire support to the Swedish Army's six mechanised manoeuvre battalions and it is expected that each battalion will have a platoon-sized unit as its main indirect fire support weapon with a total requirement for up to 24 systems.
The 120 mm FMU will replace the dismounted, conventional towed mortar m/41F systems that are currently deployed and will use 120 mm high-explosive ammunition with maximum ranges of 6,000 m (58C/58Z) and 8,200 m (86Z). It is not required to fire the Strix top attack 120 mm projectile, which will have passed its shelf life by the time the new system is introduced. Requirements include the capability to fire illumination and smoke rounds and, in the future, precision-guided versions and bombs fitted with a course-correcting fuze for increased accuracy.