The electromagnetic brake - in abbreviated form the Mg brake - is an additional brake acting directly on the rail and its operation is thus independent of rail/wheel adhesion. Its action is based on the applied magnetic force. The force applied is produced by the electromagnetic effect or by a permanent magnet. Where required, the Mg brake is fitted a coach bogies in order to supplement the air brake. The obligatory requirements of this leaflet apply to this rolling stock only. Appendix A - page 7 shows as an example a diagrammatic arrangement for the Mg brake as fitted to a bogie.