The Norbaforce came in four different versions: Marks I through IV.
Note that the breakout PCB was produced in the early days of USB C. It therefore uses a USB-C type connector but did not support USB-C to USB-C cables. It is designed for USB-C on the keyboard side and Type A on the computer side.
This was the only version to be produced with a Winkeyless option
Adds support for the R2 family of keyboards.
Data port switch to USB Mini
The Norbaforce Mark III is a third iteration of the Norbaforce housing for Realforce keyboards. Over the Mark III, the only changes are:
Inclusion of both PCBs (87U and R2) in the parts pack kit rather than those being sold separately.
Inclusion of felt acoustic dampener
Risers that fit onto the housing without having to remove the bumpons that go underneath them.
Only difference between Mark III and IV are the shape off the rubber feet cutouts so that the housings will now use v2 bumpons .