quick overview :

Specification: The metal box is double ended so that two sets of students can work independently with the same box. Slide apertures are provided which accommodate colour filters for colour mixing experiments & have blinking plates for when the slide apertures are not in use.. The box is provided with a 12V 24W straight filament lamp fixed at the centre of the apparatus while at each end is a sliding grooved frame to carry a convex cylindrical lens together with slit screen &/or filter. Long clear tracks. To triple slit screen, two blank plates for closing side aperture when not in use & 1m of twin flex. Dimensions 308 x 63 x 115 mm high supplied without lenses, filters or other accessories.