Abstract: Baffle precursors are provided which comprise a sandwich of cellular plates with a foamable material therebetween these precursors overcome the problem of the flow of the foamable material as it is heated up to cause foaming which can result in non-homogeneous foam. The baffle precursors also enable uniform baffle properties to be established on both sides of the baffle and provide improved performance for a reduction in the amount of foamable material required. The hinged cellular plate is also an aspect of the invention.