The Charge, Equipotential, and Field Mapper is an excellent addition to the Basic Electrostatics System.
Draw any set of two-dimensional conductors with the conductive ink. Investigate the electric field and the equipotential field lines between and around the conductive paper to any shape. Charge it and investigate the distribution of charge on its surface.
Similar to the Field Mapper Kit, except it includes electrometer probes, a “point charge” holder, and larger sheets of conductive paper for investigating charge distributions on conductive surfaces.