Squeamish people will have difficulty looking at these products. Many of them appear to be moving, while in reality they are perfectly still.
The effect is caused by retinal slips. They will not cause permanent damage, but they will certainly create temporary amazement.
Count the Black Dots
Make sure to view the larger image of the products. Try to count the black dots. Do they disappear when you look at them? Maybe you are just not fast enough to catch them.