Hi.
In the mid 1930th new heavy artillery pieces were developed and introduced. The parts of this guns were transported on specially designed trailers to minimise the assembly time. This trailers consisted of wo pairs of steel wheels mounted below a steel frame. The superstructure differed with the loads

barrel trailer of the type 96 150 mm heavy gun

lafette trailer of the type 96 150 mm heavy gun

traverse rails of the type 96 150 mm heavy gun

lafette trailer of the typ 96 240 mm howitzer
The end.
Yours
tom!