It's all wrapped in bubble wrap using the stretch wrap. Mine had the bases mounted when they shipped - lot of bubble wrap around the bases too, although you have to be careful not to make it too thick as otherwise the speakers won't fit next to each other in the crate.
I wish the Abbys would have come with a foam fitted to the crate - they are a real pain to move and it too about 4-5 hours to pack them properly last time. Last time I moved cross country in Canada.