This premium Van de Graaff Generator is designed to allow students to clearly see how this apparatus generates the electrostatic charge necessary to 'jump the gap'. The sphere can generate up to 200kV and can be operated both manually and by a variable speed electric motor. Adjustable discharge sphere electrostatic plume and electrostatic whirl are included.Belt housing is made out of Perspex making the unit different to most VDGs.Compliant to EN61010: 2010: certificates available on request.Sphere diameters: 225mm and 70mmHeight: 650mmBase: 250mm x 350mm