Induction annealing is the process of softening the necks of cases, through heating in an electrically contactless manner. This is achieved through placing the cases within a magnetic field, which induces eddy currents within the brass. Technically, the lower the resistivity of the brass, or the higher the intensity of the magnetic field, the greater are the eddy currents and, consequently, the greater the heating effect. There is no heating element as such; the only thing to get hot is the case. The magnetic field is focussed to maximise the eddy currents and heating in the location where it is specifically required, i.e. the neck and shoulder.