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The Garmin GT15M-IH transducer is ideal for boaters who want to install the transducer inside a fiberglass hull and not on the transom where cavitation could cause issues. The transducer can be used with a hull deadrise angle between 0° and 25° and is excellent for boats traveling at high speeds that want to maintain accurate depth readings. The 8-pin transducer with 4 plastic tanks features mid-band CHIRP traditional sonar (85-165 kHz) and has a power rating of 600W. It can be used in conjunction with a GT30-TM transducer and an adapter cable, so you can maintain depth at high speeds and scanning capabilities at trolling speeds. Maximum depth of 1,900'.