Hi,
In Poland, produced two versions of the 40 mm Bofors cannon. Version marked as wz.36 was placed on a standard basis of the Swedish Bofors. Used to it over the C2P tractor. Version determined as wz.38 while the equipment was a semi, without their own means over. Has towed by Polish Fiat 621 car or off-road wz.34. It was a semi-platoon equipment mainly used for the protection of strategic facilities. In the version of the semi-solid cannon had detachable trolley with two wheels and three folding brackets on one side.
So briefly Polish Bofors were certainly other sights and other wheels, wz.36 have a basis in the shape of a cross while wz.38 had a three-spoke basis.
Paweł