The Garmin GSD 25 is designed for the serious sport fisherman, the GSD 25 premium sonar module is a remote network solution that provides outstanding fishfinding and bottom tracking capabilities. It offers dual-channel 1kW CHIRP, plus DownVu and SideVu scanning sonar with CHIRP technology for the clearest scanning images on the water. It delivers target details so clear and precise, you can actually distinguish between small and closely spaced fish at key fishing depths all the way down to 5000 ft. Designed for use with the Garmin GPSMAP 8000 Glass Helm series or new GPSMAP 7400/7600 series chartplotters.