Garmin GSD 22 Digital Sounder Module - $479.99

Black-box sounder connects your chartplotter over the Garmin Marine Network to provide high-speed data returns and crisp detail. The all-digital design lets it transmit at up to 2kW depending on your transducer. Automatically adjust gain and transmit power for optimal returns in shallow water. The GSD 22 can connect to a dual-frequency transducer and works with standard 500-watt transom-mount transducers, heavy-duty 2kW thru-hull or in-hull transducers and can reach a depth up to 5,000 ft. Includes marine network cable, power/data cable, CANet cable, cable grommet and installation instructions.Includes: GSD22 Marine network cable Power/data cable CANet cable Cable grommet Installation instructions - $479.99