Abstract: An exposure unit for exposing photo-stencil materials in which the light box portion of the unit is continuously cooled by the vacuum pump that operates the vacuum frame portion of the unit. The vacuum pump is mounted internally of the light box portion of the unit and is interconnected with the vacuum frame by a direct interconnection so that a vacuum hose is not required. The unit also icludes a base for supporting the light box and vacuum frame which includes a light-tight, ventilated storage area for the storage of light sensitive materials.