Präzisa ribbing attachment, similar to Präzisa knitting machine, was manufactued by the Western Germany company in the late 1950s to early 1960s.

Präzisa ribber accesorizes Präzisa knitting machine, converting its into a double-bed. The manual for this ribber is available online for mree.

From what I see so far, it seems that there is one ribber needle per every two main bed needles. The three pictures below show Präzisa ribber (and ribber carriage) inside the Präzisa machine. You can see the gauge difference. I think such design was created