You mention XNT 9 20 T so I assume you have Helix 7 CHIRP DI GPS G2N ...
There is a TM version of the same xducer XTM 9 DI 25 T ...
If your HELIX has a Connected Transducer selection under the Sonar tab of "HB + 83/200" - you can also use the XTM 9 WIDE DI 20 T (which has wider 2d sonar cones) ... XTM 9 WIDE DI 20 T is also a TM version ...
-----
XHS 9 HDSI 180 T is a side imaging xducer that will not work correctly on the DI unit ...
Rickie