New Transducers 250C - Manual (Page 39)

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Fishfinder 250/250C Owner’s Manual 35
Thermoclines
One feature unique to Garmin is See-Thru
®
technology. See-Thru
technology allows the Fishfinder 250/250C to “see” through
thermoclines and locate fish where they live—and fish love
thermoclines. A rough definition of a thermocline is a break in the
water where the temperature changes faster than in the water above
it. Thermoclines give weak returns and are shown as the weakest
colors/shades (page 15).
Thermocline