Back To The Future BTTF Plutonium Chamber. Plutonium chamber prop from back to the future. Made of acrylic and sealed to be able to hold water. The top disc rotates so you can fill it with water (it will ship without for safety). Bottom rotates to drop the plutonium out like in the movie. The chamber portion is about 6 1/4 inches tall with the tube sticking out about 1/4 inch. The plutonium stick is about 7 1/2 inches tall