Original 1949 window trade vintage catalog for the PITTSBURGH PLATE GLASS COMPANY. 

Manufacturers of Twindow - The Window with Built-in Insulation.

Twindow Insulating Units are completely prefabricated and consist of two or more pieces of glass enclosing a small hermetically sealed airspace. Hollow aluminum tubing separates the pieces of glass. The entrapped air is at atmospheric pressure. It is dehydrated initially by means of a drying agent within the spacer tubing , which has access to the air through the holes adjacent to the internal corners. This desiccant provides added insurance against the slightest vapor diffusion.

Has product images, illustrations, description, applications and specifications to provide product details.

Unbound from a large rare 1949 Architectural Catalog for Builders, this unique old four-page technical brochure would display beautifully matted and framed. Nice graphics. A fabulous addition to your retro window library.