dfSpecifications: This ?Light In Glass? set is used for the study of the reflection of mirror. Users can observe that the light bulb is submerged under the water because the bulb reflects with the mirror which creates a shadow in the water tank. It makes us seems that there is a light bulb illuminating in the glass. The reflection of the mirror is only a partial reflection, which explains the picture that users see. This set consists of a rectangular box is of dimensions 40x40x40 cm. All of the 5 sided are opaque, only one side is left half transparent. Inside the box, consists of a light bulb 220V, and one sheet of mirror, and one glass. The mirror is placed between the bulb and the mirror. This device uses 220VAC 50Hz. The switch and the fuse are installed at the base.