Heading SensorProvides heading data, just like a traditional compass. GPSNo requirement for a separate GPS antenna - this one delivers an extremely fast fix and excellent in-band and out-of-band interference rejection. Rate of Turn SensorThis smart sensor calculates turn rates for precision heading and positioning whilst underway. Integrated Gyro and Tilt SensorsDeliver fast start-up times and provide heading updates during temporary loss of GPS. COAS