Garmin Marine Heading SensorWhen interfacing this three axis compass heading sensor to Garmin? s marine lineup of MFDs and radars, mariners can expect unparalleled radar overlay performance and accuracy along with excellent MARPA capabilities. This heading sensor (based on Airmar H2183) uses a rate gyro, so it can maintain an exceptional 2 deg. heading accuracy under heavy dynamic conditions, with up to 30 deg of pitch and roll. In addition, it supports either NMEA 0183 or NMEA