Good point.. it's the full assembly, the "Rohloff Axle Ring Assembly for Rohloff Speedhub 500/14 - 8572" (according to SJSC)
It has the black plastic outer. meaning there's no winding of wire around the inner brass ring required. It means you can do a roadside repair without any winding of inner wire (which is painfully tedious).
It's a part only of interest to internal shift hubs (the one WITHOUT the external shifter box).