Abstract: There is provided a sealing apparatus for forming void-fill packaging which includes a longitudinal guide path along which an edge of a part-sealed plastics film material can pass, a drive means for moving the film material along the guide path, and an air blowing or injecting means for inflating the film material. There is also provided a heating element and a rigid thermally conductive member which is thermally coupled to the heating element, the thermally conductive member having an film-contacting surface for applying thermal energy to seal the film material on the longitudinal guide path.