You will be UNABLE to use any switch with the Mega SI unit, the current 2D XDCR supports 175-225 kHz Chirp.

9 M SIDB Y | Cables | 720101-1

​Y Cable - Side Imaging and Dual Beam - allows you to use two transducers on one unit without the use of a transducer switch. For use with Side Imaging products only, in conjunction with a dual beam transducer only. For improved high speed performance for bottom tracking. 30"

SUPPORTS MEGA SIDE IMAGING