Garmin - GSD 26 Digital Remote Sounder Module

 
For serious deep-sea sportfishing, the GSD 26 takes high-definition targeting to a whole new level. With a compatible transducer, the GSD 26's Spread Spectrum technology scans on multiple frequencies at one time, returning vast amounts of data to the receiver. As a result, you can expect precise, shallow-water-like target separation at much greater depths up to 10,000 ft (3,000 m). A traditional fixed frequency mode allows you to manually adjust frequencies from 25 kHz to 210 kHz for enhanced targeting of specific fish species. You can also adjust transmit power from 300 W to 3 kW (depending on transducer) for even more control over your sonar returns. Features dual-transceivers which allow simultaneous and independent transducer operation.