I do not read or speak German so I do not know what this indicates, maybe nothing, but in the product lineup for analog cameras it shows only the MZ-M, MZ-60, ist.
http://www.pentax.de/pentaxeurope/pentaxeurope_prod/pentaxeurope/v2/de/photo/cameras/singlelensreflex/index.html In the product archive it shows the MZ's 3, 6, 5n and S http://www.pentax.de/pentaxeurope/pentaxeurope_prod/pentaxeurope/v2/de/photo/archiv/cameras/single%20lens%20reflex/index.html (sent this earlier. not sure why it is not posting.)
