Playsteam loves to create toys that teach so kids can learn concepts of science, physics and mathematics. This toy uses a device that winds up a string on one end of a ring. When the ring is pulled, it spins the arm that holds a double sided card with image.
The trick is that the card has 2 images that flash quickly when spun on this device and it makes an image with both of them. Our eyes are not quick enough to see the difference when card is spinning and it tricks our brains into thinking the images they are combined. This set comes with 3 cards with double sides to created a mind blowing image.