Here is what I found on Amazon when looking up the part number you provided. Appears it comes with everything you need.
Humminbird XHS 9 HDSI 180 T Transom Mount Transducer
•New design is more secure, less prone to kick up, with improved running angle
•Includes 20-foot cable, necessary mounting hardware, and built-in temperature sensor
•Combination DualBeam 20- and 60-degree beam sonar, and side-imaging sonar with two 84-degree beams
•Compatible with 997c SI Combo fish finder and other side-imaging Humminbird sonar systems
•Backed by manufacturer's one-year limited warranty
•83/200/455/800KHz
•60°/20°/180° beam angles
•Transom mount
•For Side Imaging units only
•20-Feet cable