A novel composite microtubing with variable stiffness over the length of the tubing and continuous process for manufacturing the same is provided. The chassis includes a front plate, a rear plate, a top plate, two side plates, a bottom plate and a plurality of dividing plates. Thus, even when radio communication parts are disposed in a plurality of terminals, by using the pseudo radio communication control part instead of a radio communication control part, an application can carry out control as though all the radio communication parts were connected in the same terminal. In turn a complementary spigot ring is provided with a welding lip having an outer diameter that is between the larger and smaller diameters of the bell plate ring. The multi-layer core comprises at least one intermediate core layer formed from a metallic, composite, or inorganicorganic hybrid composition.