Diffusers for skylights (translucent building panels); mounts of concrete for skylight windows; mounts of plastic for skylight windows; mounts of wood for skylight windows; non-metallic frames for skylights; non-metallic skylights for buildings; plastic skylights; skylights (windows) of non-metallic materials for use in buildings; skylights made from plastic materials for use in buildings; skylights not of metal (windows); translucent building materials for skylights