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 that Eliminate the Dead End Cellar, for Residence and Sidewalk Doors. Made in Three Designs, Each in Three Stock Sizes, Style O-3, O-2, and O-1. Disbound from a large 1941 construction materials book, this unique old two page technical specifications brochure would make a sensational addition to your retro architectural design and engineering library. Contain a small amount of residual glue on edge.