Humminbird AS GPS HS Precision GPS Antenna w/Heading SensorGPS ANTENNA W HEADING SENSOR AS GPS HSPrecision GPS Antenna w Heading SensorSee compass information and your boat's orientation while moving or sitting still with this integrated heading sensor and GPS antenna. (Standard with 360 Imaging) Provides accurate Course Over Ground (COG) reading and position fixes within 2. 5M, even in lower signal areas. When used with 360 Imaging, provides the ability to mark accurate waypoints anywhere on the screen.