The Super Rotax R89 in slot 6 was a school pen available in the early 1970s. I remember using them and they were considered a step up from the Heros of the time. In those days they were sold in bookstores and sundry shops in Singapore.
There was another model in black, also a piston filler, just called Rotax (can't remember the model number) that was cigar shaped.
Rotax was distributed by Mutschler GmbH which also sold Reform pens. It is believed that Rotax was designed by the Excelsior Fountain Pen Company, a subsidary of Montblanc.
The Super Rotax was available in 4 colours, dark grey, sky blue, burgundy and green and came in gold cardboard display boxes. Mine are shown below, a reminder of my school days.