The built-in sonar capabilities of the GPSMAP 7408xsv include 1 kW dual CHIRP sonar, the most sophisticated sonar technology available for the fishing and boating public. Dual CHIRP sonar provides amazingly clear target separation and definition because it puts even more energy onto the target than CHIRP. It gives you the ability to show low/high, med/high or low/med on the screen at the same time, enhancing your ability to distinguish between game fish and balls of bait fish. It also includes both CHIRP ClearVü and CHIRP SideVü scanning sonar that provide nearly photographic sonar images of fish and structure that passes below and to the sides of your boat. Garmin ClearVü™ and Garmin SideVü™ provide the clearest scanning sonar images on the water. Also supported are 50 kHz/200 kHz, 77 kHz/200 kHz and Minn Kota® and MotorGuide® trolling motor transducers (sold separately). GPSMAP also includes sonar-recording capability that coordinates the timing of the sonar return with your boat's position and saves digital information for playback on a computer using HomePort™ planning software.