Helmholtz Coils are a special arrangement of coils that are placed in such a way as to generate a very uniform magnetic field between them when a current is applied. The strength of the magnetic field is proportional to the number of turns in the coils and the current applied to them. The BESTO Helmholtz Coils setup consists of two field coils mounted on a track to provide a uniform magnetic field between the coils. The proper separation for Helmholtz coils is marked on the track.