Garmin 010-12402-10 GT15M-TM Transom-Mount Transducer with Mid-ChirpPerfect for fishermen who want clear bottom definition under the boat Provides crisp, clear and wide fish arches with excellent target separation to depth up to 1, 900 feet Features mid band CHIRP traditional sonar (85 165 kHz) Power Rating: 600 W Transom mount installation GT15M TM transducer is perfect for fishermen who want clear bottom definition under the boat as well as crisp, clear and wide fish arches with excellent target separation to depth