MONDIA rare gents wristwatch with slide rule

MONDIA rare gents wristwatch with slide rule and rear site world time in steel, Switzerland around 1965, self winding, screwed down case, in case back adjustable world time-display, crowns at 2 & 4 for inner & outer slide rule- ring, silvered dial, silvered luminous indices & hands, day & date at 3, diameter approx. 42 mm, overhaul recommended at buyer's expense, condition 2-3, from the estate of a collector