Meet the Garmin GT15M-IH In-Hull Transducer, a mid-band CHIRP transducer designed to install inside a fiberglass hull. This smart placement eliminates cavitation concerns on the transom while delivering rock-solid depth readings at high speeds. With CHIRP coverage from 85–165 kHz and a robust 600 W transmit power, the GT15M-IH is built for accuracy where it matters most.

Why choose the GT15M-IH

• In-hull installation reduces cavitation risks and preserves hull integrity, ideal for high-speed boats.
• Mid-band CHIRP sonar provides clear, detailed depth and bottom information across a wide range of conditions.
• Compatibility works with the GT30-TM transducer and an adapter cable to maintain depth at high speeds and enable trolling-speed scanning.
• Deadrise versatility supports a hull deadrise angle between 0 and 25 degrees.
• 8-pin connection with 20 ft cable for flexible mounting options.
• Excellent beam performance with beam widths of 24° (LF) and 13° (HF) for balanced target separation and bottom tracking.

Specifications

• Frequency: CHIRP 85–165 kHz
• Beam Width (LF/HF): 24° / 13° (-3 dB)
• Transmit Power: 600 W
• Water Temperature Sensor: No
• Cable Length: 20 ft
• Connector: 8-pin

What's in the Box

• GT15M-IH transducer
• 4 plastic tanks
• Mounting hardware
• Documentation

Installation note: Follow the included instructions carefully to avoid damaging your boat. The GT15M-IH delivers reliable, high-performance depth readings while keeping the transducer protected inside your fiberglass hull.