XTM 9 WIDE DI 20 T ...:
*200kHz 20°/83kHz 60° 2d conical beams
*800kHz 45°/455kHz 75° DI fan beams
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XTM 9 DI 25 T ...:
*200kHz 28°/455kHz 16° 2d conical beams
*800kHz 45°/455kHz 75° DI fan beams
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The wider 2d beams in the XTM 9 WIDE DI 20 T will give more coverage under your boat ...
Rickie