The David White Stereo Realist ST-63 viewer is a handy, small-sized but high quality LIGHTED stereo slide viewer.
The light goes on when the slide is pressed down.
The lenses can be focused.
This cleaned and serviced viewer comes with an LED-BULB included for best viewing.
These viewers were built for Realist format slides, so 5P.
Full frame stereo slides can not be seen entirely in this viewer.