Photovoltaics Equipment Set Accessories. Supplement to the Photovoltaics Equipment Set. For the investigation of: Electrical loads, Series and parallel connection of incandescent lamps, Direction of rotation and velocity of an electric motor, Brightness, Diffuse radiation, Albedo radiation, Rotating discs, Color mixing, Color illusions. Contents: 1 Plug-in horn, 1 plug-in incandescent lamp, 1 plug-in motor, 1 set of 5 rotary discs including holder. Weights: 1.33 pounds.