<b>M001 Digital In/Out</b>, extension module (cartridge) for the East German home computer <a href="https://en.wikipedia.org/wiki/KC_85" class="extiw" title="en:KC 85">KC 85/2</a> and its successors, manufactured by the <a href="https://en.wikipedia.org/wiki/Kombinat_Mikroelektronik_Erfurt" class="extiw" title="en:Kombinat Mikroelektronik Erfurt">VEB Mikroelektronik</a> "Wilhelm Pieck" Mühlhausen.
Enrico Grämer
Attribution
The author sent the photo to me.