A collapsible, extendable compact information display device includes front, rear, and side rectangular wall panels formed from a unitary blank and joined by self-hinges so as to be transferable between a lay-flat and extended parallelepiped condition. The front wall panel is separably joined to an adjacent side wall panel by a flap having glue or a pressure sensitive adhesive. Information in a highly reduced scale is carried on opposite faces of the rear wall and the separable side wall panels and is selectively viewable through a lens mounted on and registering with a central opening in the front wall panel by adjusting the relationships of the wall panels.