King Swallowtail caterpillar

It looks like a bird poop to get away from predators, it inflates the osmeterium (that looks like antennae) and exude a horrible smell that comes from ingested oils from the plant, making it seem unpalatable. I've got four other caterpillars of the same species on the same tree, but in different instars. I have a video of it expanding the ometerium, but for some reason I can't put youtube video here.