To seal a gap between the panel 6 and the roof aperture a plastics part 12 is provided on the outside of the support 5 to which the panel is secured. The part 12 can be so adjusted relative to the support 5 after panel installation that one edge 19 of the shield part is reliably applied against a seal 10 on the longitudinal edge of the panel or roof aperture. Parts 12 are provided at each longitudinal side of the panel. <IMAGE>
