Not Your Average Rubber Ducky. Kids are all different shapes and sizes, shouldn't rubber ducks come that way too? Meet Slim, Bob, Jane and Squish. We're not trying to encourage a rubber ducky smackdown, but Odd Ducks are PVC-free, unlike those other mucky ducks. And ours do not hold water, so they won't grow that black mold that kids always try to suck out.