The Garmin GT15M-THF brings mid-band CHIRP sonar to thru-hull installations on midsize fishing and cruising boats. Its stainless steel housing mounts flush through the hull — no fairing block needed — and the 12-degree tilt design handles hull deadrise angles from 8 to 15 degrees across fiberglass, composite, steel, aluminum, and wood construction. Depth readings reach 1,200 ft in saltwater and 1,900 ft in freshwater, while Garmin Auto-ID lets a compatible chartplotter recognize and configure itself to the transducer the moment it's connected.

Specifications:

• Transducer Type: Mid-band CHIRP traditional sonar
• Frequency Range: 85–165 kHz
• Power Output: 600 W
• Beam Width: 16–24 degrees
• Maximum Depth: 1,200 ft saltwater / 1,900 ft freshwater
• Cable Length: 50 ft
• Sensing: Depth and temperature
• Connector: 8-pin
• Supported Deadrise Angle: 12-degree version accommodates 8–15 degrees of hull deadrise
• Compatible Hull Materials: Fiberglass, composite, steel, aluminum, wood
• Housing Material: Stainless steel
• Mounting Style: Thru-hull flush mount

In the Box:

• GT15M-THF transducer
• Jam nut
• Washer
• Thread isolator
• Hull isolator
• Documentation

Resources:

• Installation Guide (PDF)