The specimen on display in the museum is composed of four cylindrical bottles (diameter 11.6 cm, height 20 cm) with narrow necks which differ from traditional ones since the inside plates consist of loosely rolled and bent tin foil and the metal rods on the outside are not connected to each other; three of them are bent while the fourth is straight and ends with a round pommel. This allows for different connections and thus is more useful for teaching purposes. The bottles can be used not only singly or in groups, up to a maximum of four, in parallel, but also in groups of two in parallel and these together in series, two in parallel and two in series with one of the others and, finally, three in parallel and in series with the fourth.