www.securitymagazine.com/articles/77408-discreet-viewing-panel-1
Discreet Viewing Panel
September 1, 2005

U.K.-based Vistamatic’s vision panel comprises clear and opaque sheets of glass in a single frame. It is easily opened or closed with an integral lever or knob mechanism to reveal or obscure the view into or out of a room as required. Once installed, the vision panel is maintenance-free and, because it is effectively triple-glazed, sound transmission is kept to a minimum.