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As the boat moves, the unit charts the changes in depth on the display to create a profile of the Bottom Contour. The type of bottom can be determined from the return charted on the display. A Hard Bottom such as compacted sediment or flat rock appears as a thinner line across the display. A Soft Bottom such as mud or sand appears as a thicker line across the display. Rocky Bottoms have a broken, random appearance.
Bottom Contour Profile with RTS® Window.
Temp/Speed Accessory is optional.
Hard Bottom
Rocky Bottom 
Soft Bottom
The sonar returns from the bottom, structure and fish can be represented as either Inverse (default), WhiteLine®, Structure ID®, or Bottom Black. See Sonar
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