Large IES Reflector Shades are made of white waffle pattern, glass. These glass reflector shades provide a superior translucent quality. They glow when lit, providing generous illumination. The fitter opening will slip over a mogul socket. Mogul sockets are the large porcelain types found on many vintage floor lamps. The "IES" initials are an abbreviation for "Illuminating Engineering Society."
Glass Reflector Shades are dual purpose lampshades. They act as a light diffuser dispersing and directing light upward. In addition IES reflector shades are often used to support large fabric, parchment or mica lamp shades on table and floor lamps. The large secondary shade is kept in place by V notches in top of shade ring.