According to the AOHC magazine "SPOTMATIC" n°33, page 15, Reflex Pentax 1952-2002 by Dario Bonanza: Z-20 and Z-70 have been sold in Japan with panorama features only (Z-20p/1993, Z-50p/1995) I read too a MF body, industrial version of ME in half-format (18x24mm)
Michel