Garmin GPS 24xd GPS Antenna with Heading Sensor (NMEA 2000)
The Garmin GPS 24xd is a multi-band GNSS, high-sensitivity GPS antenna with heading support designed for NMEA 2000 marine networks. Buyers report noticeably improved position accuracy and heading usefulness compared with relying on an internal GPS, but it is a specialized add-on if your setup already has an appropriate NMEA 2000 chartplotter or network.