Original concrete trade vintage catalog for MASTER BUILDERS COMPANY of Cleveland, OH. Manufacturers of concrete floor hardner (hardener) used for making concrete floors dustproof, wearproof and waterproof. The new Red Hardner is a combination of regular with a specially manufactured pure metallic red color. Disbound from a large 1916 engineering book, this unique one page technical specification brochure would display beautifully matted and framed. Contains a small amount of residual glue on edge.