The M1129 Mortar Carrier, also known as MCV-B (Mortar Carrier Vehicle version B), is based on the Stryker infantry carrier vehicle, which is itself a descendant of the Swiss Mowag Piranha III.
The precursor of the M1129, the MCV-A, carried a mortar that could only be used dismounted, whereas the M1129 is fully capable of firing its weapon from the mounted position within the vehicle.
The MC provides accurate and lethal high angle fire to support operations in complex terrain and urban environments. The MC accommodates a 120mm mortar system that fires a full family of mortar ammunition (HE, illumination, IR illumination, smoke, precision guided,) while mounted.