The magician places a silver colored disk in a frame with cut-out sections by which the spectators can see through the frame. A silver colored disk is put into the frame and is seen through the cut-out sections both front and back. The magician then snaps his fingers and instantly & visibly the disk changes colors! The disk is removed from the frame and is seen to be a different color.
This is repeated with two more silver disks which are changed into two other colors.
The effect is like the color changing records, but works on a different principle. Still easy to do.