Specification optical glass. Size: 20 mm x 20 mm x 2 mm. Package includes: 1 x RGB prism optical glass prism It's lightweight. And that is, three red, green and blue lights, respectively the base light, of the remaining surface emitting which is the light Optical Glass RGB Prism, there are four lights, in of the lighting inputs of the lighting surface, from the three remaining lights, three basic colours red, green and blue, respectively, are said three bases of the light It is of the most important accessories on the projector, the projector is capable of projecting color shadows on the screen, you need to know which color of light is composed of three primary colors on the screen, an important color Prism colors Can be used as teaching tools or research and decoration, they are very beautiful, Manufacturer: KACCDE