Key features of the GS25 NMEA 2000 antenna module offers rugged and precise position, and heading sensor Spot-on, around-the-world accuracy -- supporting GPS and GLONASS, WASS/EGNOS/MSAS; Galileo-capable with future software update Excellent time-to-first-fix, with 10-hertz, multi-GNSS, high-speed updates - up to 10 times per second -- for smoother and more accurate location updates Integrated electronic rate stabilized compass to provide chart stabilization, accurate course over ground at low speed, and radar overlay Rugged design for all marine environments and fully waterproof Include spat/pole mount for easy installation and flexible boat location for optimal performance Independent source selection on any display Note: Not suitable for MARPA or Steering of an Autopilot. Please use a Precision-9 compass or GPS Compass.