Shows two similarly charged objects repel. This features an aluminum case with 4mm socket, a ground terminal and gold leaf support insulated by Teflon. It is provided with a scale to measure the deflection of the gold leaf when static electricity is induced, making it a quantitative device. Design consists of two interchangeable electrodes, a disc top plate and a metal hook. We include an internal transparent scale divided 0 to 90 C x 10 C on the rear glass wall.