Using this optical prism, you can do a lot of interesting physical experiments. For example, you can repeat Newton's famous experiment, in which he discovered that white is a mixture of colored lights. For this, he covered the window of his room to darken it. He then cut a slit in the window cover to allow only a tiny stream of light in. He held his prism in the light and noticed a rainbow on the opposite wall. He concluded that white light is a mixture of all the colors he saw. This is of course not the only experiment you can do, English instructions for more experiments are included.
The optical prism is about 6cm high and about 3cm deep. It comes in a representative plastic box.