Garmin 010-12219-00 GT21-TM Transom Mount DownVu Transducer with Temperature Sensor (8-Pin) Provides ultra-clear sonar pictures of objects, structure and fish that pass below your boat This traditional and CHIRP DownVu transducer is optimized for depth performance and rough conditions CHIRP DownVu element has a power rating of 500 W and operating frequencies of 260/455 kHz, traditional sonar has a power rating of 600 W and operating frequencies of 50/200 kHz Built-in fast response temperature sensor Includes an 8-pin transducer with mounting hardware and installation instructions