The invention relates to a stamped or braided form of a solid material or foil that can be inserted into a tank or container, for example to prevent an explosion of fuel inside the tank. Various combinations of materials can be used to produce the forms and braids. In a preferred embodiment, two or more stamped, helical forms of a metal foil material are interlocked or linked together, and a wire or fiber is placed at least partially in the center of one of the helical forms. This structure presents advantageous properties when used in fuel tanks, and resists deformation. In addition, certain forms or structures can be designed and used so they can be easily removed from the container or tank.