Original concrete trade vintage catalog for SECURITY INSERT COMPANY, was located on Thirty-Third at Arch Street, Philadelphia, PA. Manufacturers of ceiling sockets for concrete work. Solves the problem of the handing of machinery or fixtures to be suspended from ceiling or wall in factories, warehouse and other buildings of concrete consturction. Shown are bolt and nut in position, bottom view of insert with cardboard disc for concealing hole when desirable. Disbound from a large 1916 engineering book, this unique one page technical specification brochure would display beautifully matted and framed. Nice graphics. Contains a small amount of residual glue on edge.