This apparatus set is used for the study of mixing of colors on a white screen, that can be seen through the mirror. It is also used to the study the properties of colored filters with red, green, and blue colors. There is a switch to choose to mix the colors, the mixing box is capable of mixing 2 or 3 colors at the same time. The screen is able to slide in/out, the focal point is adjustable. There is a fan to drain out the heat uses 220V A.C. There is also a fuse preventing the current to short circuit.