Darkness and Light 2-pack
The Particle Zoo
The best of both worlds! Contains a Dark Matter and Photon, the lightest and heaviest particles in the Zoo (theoretically speaking).
Approximately 19 oz (0.5 kg).
For ages 5 and up as it contains glued-on/small parts.
The Darkness and Light 2-pack is available in a lightweight shipping saver version which is especially nice if you live outside the U.S. Both plushes will be filled with lightweight stuffing. Of course you won't get the full effect of their varying weightiness, but they will be the same in every other way.