Field Guns are unpropelled vehicles built at a Garage or produced at a Mass Production Factory. They must be pushed by their two crew members to be moved. They have a heavy front shield to protect their crew. They do not have Tank Armor and thus cannot deflect incoming projectiles. They are the only vehicle type to use the same visibility system as infantry: they are invisible at night and can be hidden behind solid obstacle and in large bushes. They are small enough to fit on a Flatbed Truck once packaged.
Unlike motor vehicles, which wont freeze during a Snow storm if their engine is on, field guns shall get frozen even if crewed and moving in the middle of a road (they stop suddenly).
A third soldier can stand on the rear part of the gun to be carried by it. That additional soldier can be useful to the crew through spotting with binoculars.