Original door trade vintage catalog for BILCO MANUFACTURING COMPANY. Main office and factory was located at 164 Hallock Avenue, New Haven, CT. Manufacturers of All Steel Bulkheads for Residences, also Sidewalk Doors. 12 gage copper steel designed to last as long as the building itself. Disbound from a large 1938 construction materials book, this unique old two page technical specifications brochure would display wonderfully matted and framed. A marvelous addition to your retro architecture design and engineering library.