NO MORE SONAR,..? OR BOTH..
A MEGA DI transducer does three different Imaging frequencies and 2D sonar.
Have not seen the specs, but the current MEGA DI transducers have the Low-Q Dual Spectrum CHIRP 2D crystal—-140-240 kHz.
Humminbird Helix 12 CHIRP SI, 1198c SI, 1198c SI, ONIX 10 SI NT, Helix 7 CHIRP SI GPS G2, SOLIX 12 SI, 360, RC-1