honeycomb core structure 1 provided with several cavities 2 and some of the cavities contain cylinders of foamable material 3 the cavities which contain the foamable material are tapered so that they hold the foamable material in place the structure shown in fig1 is designed to reinforce a door and is provided with clips 4 to enable it to be attached to the door frame fig2 shows three of the structures illustrated in fig1 attached to the door frame to provide structural reinforcement fig3 shows an injection moulded part 5 provided with cavities 6 some of which contain cylinders of foamable material 7 the part 5 is designed for reinforcement of an automobile longitudinal section and fig4 is a cut away view of an automobile longitudinal showing five parts 5 in place to provide reinforcement in operation of both systems the parts may be mounted in the appropriate location in the vehicle during body assembly the body may then be subjected to anticorrosion treatment such as the e coat electrocoat process and then baked to cure the coating the foamable material may be formulated so that it will expand and develop adhesive properties under the baking conditions in his way the foamable material will.