US Army M109 Self Propelled Howitzer
This is a motorized kit produced by Nichimo perhaps in the early 1970s. The kit contains a RE-26 motor and is unique in that the gear box can be configured into three different gear ratios. It can also be upgraded into a wired remote controlled model, but the control unit was not included in this kit.
The M109 is an American 155mm self-propelled howitzer, first introduced in the early 1960s. It was upgraded a number of times to today's M109A6 Paladin. The M109 family is the most common Western indirect-fire support weapon of maneuver brigades of armored and mechanized infantry divisions.
The M109 has a crew of six: the section chief, the driver, the gunner, the assistant gunner and two ammunition handlers. The gunner aims the cannon left or right (deflection), the assistant gunner aims the cannon up and down (quadrant). The M109A6 Paladin needs only a crew of four: the commander, driver, gunner and ammunition loader. - from Wikipedia