Lestrade Simplex Stereoscope 3D Viewer (1966)
French made. With 12 viewing cards.
@MrRobotoUK There are various others that use a similar slide setup from around that time (50s-60s) but different designs. I would think they are compatible but you never know.
@dgibb01 fair enough...slightly before my time I guess. :p
@MrRobotoUK Not gonna get any of those 80s TV show reels here.