The Garmin GT15M-THF is a flush-mount, stainless steel thru-hull transducer engineered for midsize fishing and cruising boats. Running mid-band CHIRP sonar at 85–165 kHz, it delivers sharp fish arches, clear bottom returns, and reliable depth readings down to 1,200 ft in saltwater and 1,900 ft in freshwater — all with minimal hull drag. Garmin Auto-ID technology handles setup automatically when paired with a compatible chartplotter.

Specifications:

• Transducer type: Mid-band CHIRP traditional sonar
• Frequency range: 85–165 kHz
• Power output: 600 W
• Beam width: 24–16 degrees
• Maximum depth: 1,200 ft saltwater / 1,900 ft freshwater
• Cable length: 50 ft
• Sensors: Depth and temperature
• Connector: 8-pin
• Supported deadrise angle: 0-degree version accommodates hull deadrise angles from 0° to 7°
• Housing material: Stainless steel
• Compatible hull materials: Fiberglass, composite, steel, aluminum, wood

In the Box:

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

Resources:

• Installation Guide (PDF)