"CLIPPER ELECTRONIC STEERING COMPASS is a fully electronic compass with remote fluxgate sensor. The large clear display has 7 levels of illumination and give True or Magnetic heading. The sensor which is gimballed for plus/minus 45 degrees of pitch and roll, is mounted in a position where stray magnetic fields are at a minimum. An electronic auto calibration then cancels out small errors. An off course alarm provides a safety feature when not at the helm. If the heading deviates by more than a preset amount then the alarm will sound. Steer-to-Course Function- when the steering function is selected a series of chevrons accumlate showing the magnitude and direction of the steering error. To stay on course simply turn the wheel in the direction of the chevrons until they disappear."