How fragile are we talking, and what are we talking about? It's hard to imagine a huge, fragile prop, since most things of a larger size need to be of at lease a somewhat tough material if only to support its own size/weight. If you give us more of an idea on what it is exactly you are trying to pack up, we can probably give you some better suggestions. (As an example: my recommendations for transporting a replica mirror from Snow White and the Huntsman would be very different than recommendations for transporting a life-sized stuffed-but-brittle Chewbacca mannequin.)