Anyway, for travel there are two things you will probably want: body caps (front and rear) and there is also a gizmo that locks the mirror in place. I have been thinking of re-rigging all the knobs so they will pop off... they are the only thing that keeps the capped body from being a perfect cube, which more convenient for packing.
One more thing, especially pertinent to travel if weight is a major concern: the prisms are way heavier than they should be IMHO. So you'll want a compact hand meter, plus an understanding of the bellows factor chart on the side of your rb. On the other hand, I often lift my rb by the prism and it's never broken so... (by now you will have gotten the picture that I really don't treat my gear specially)
One thing I have succeeded in breaking on the rb system: the dual cable release. So I try to keep spares and normal releases just in case. But I have unnaturally strong fingers, apparently... I break cable releases all the time.
If you start to acquire rb lenses then you will quickly realize that this is where the weight is, when you pack for travel! A one lens kit is no big deal. But pack a 65, 127 and 210 or similar kit and two backs... :rolleyes: