Original roofing trade vintage catalog for INTERLOCK FLASHING CORPORATION. Main office was located at 101 Park Avenue, New York City, NY. Manufacturers of Double-lock copper roof flashings, eliminates seepage through brick or stone work in parapet and other masonry walls. Unbound from a large 1933 architectural catalog, this unique old one page technical specifications brochure would display beautifully matted and framed. Nice graphics. A fantastic addition to your retro roofing construction library. Light damp stain on top and bottom edges.