Original heating trade vintage catalog for H. H. ROBERTSON COMPANY. Main office was located in Pittsburgh, PA. Manufacturers of roof ventilators, skylights and sidewall sash. Numerous images and charts with dimensions are provided. Unbound from a large 1933 architectural catalog, this unique old three page technical specifications brochure would display beautifully matted and framed. A fantastic addition to your retro roofing construction library. Pages are detached and may contain a small amount of residual glue. Damp stains on page edges and some bleed through.