Garmin GT12M Bronze Thru-Hull Transducer - 350W Mid-Band CHIRP with 12° Tilt and Temperature Sensing
Optimized Mid-Band CHIRP Performance for Moderate Deadrise Hull Designs
The Garmin GT12M-THF Bronze Thru-Hull Transducer with 12-degree tilt delivers exceptional sonar performance specifically engineered for midsize fishing and cruising boats with moderate hull deadrise angles. This premium 350-watt mid-band CHIRP transducer provides crystal-clear fish detection, precise structure definition, and accurate depth readings down to 1,200 feet in freshwater and 800 feet in saltwater.
The 12-degree tilt configuration is perfectly designed for vessels with hull deadrise angles from 8 to 15 degrees, ensuring optimal sonar beam orientation perpendicular to the water surface. Combined with durable bronze construction and flush-mount thru-hull design, this transducer delivers professional-grade performance while minimizing drag and maximizing fishing success.
Advanced CHIRP Sonar Technology
350-Watt Mid-Band CHIRP
High-definition mid-band CHIRP sonar operates across 85-165 kHz frequency range, providing exceptional target separation and crystal-clear fish arches for superior underwater visibility.
12-Degree Tilt Optimization
Precisely angled for hull deadrise angles of 8-15 degrees, ensuring optimal sonar beam orientation and maximum performance on popular V-hull boat designs.
Bronze Thru-Hull Construction
Durable bronze housing and stem provide superior corrosion resistance and flush-mount installation for minimal drag and optimal hydrodynamic performance.
Dual-Function Capabilities
Combines high-performance depth measurement with fast-response water temperature sensing for comprehensive underwater environmental information.
Detailed Technical Specifications
| Model Number: | GT12M-THF (010-02867-01) |
| Power Output: | 350 watts |
| Frequency Range: | 85-165 kHz (Mid-Band CHIRP) |
| Beamwidth: | 16-24 degrees |
| Maximum Depth: | 1,200 ft freshwater / 800 ft saltwater |
| Housing Material: | Bronze with anti-corrosion treatment |
| Installation Type: | Thru-hull flush mount |
| Tilt Angle: | 12 degrees |
| Supported Deadrise: | 8-15 degrees hull deadrise |
| Cable Length: | 50 feet |
| Connector: | 8-pin transducer connector |
| Temperature Sensor: | Fast-response thermistor |
| Hull Compatibility: | Fiberglass, composite, wood |
Hull Deadrise Angle Optimization
Why 12-Degree Tilt Matters
The 12-degree tilt angle is specifically engineered to accommodate popular V-hull boat designs with moderate deadrise angles. This precise angle ensures the sonar beam remains perpendicular to the water surface, maximizing sonar performance and accuracy.
Optimal Hull Compatibility
8-15 Degree Deadrise Hulls
- Sport fishing boats
- Center console vessels
- Cruising boats with moderate V-hull design
- Walkaround fishing boats
- Express cruisers
Performance Benefits
- Optimal beam angle for fish detection
- Improved bottom tracking accuracy
- Enhanced structure definition
- Maximum sonar sensitivity
- Reduced noise and interference
Superior Sonar Performance Features
High-Definition Fish Arches
Mid-band CHIRP technology delivers crisp, well-defined fish arches that make it easy to distinguish between small baitfish and larger target species. Enhanced target separation helps identify individual fish within schools.
Excellent Structure Definition
Superior sonar sensitivity and low noise performance provide clear definition of underwater structures, bottom composition, and habitat features critical for successful fishing strategies.
Wide Coverage with Precision
The 16-24 degree beamwidth provides excellent coverage while maintaining target resolution, perfect for scanning large areas and locating productive fishing structure.
Temperature-Based Fish Finding
Real-time water temperature sensing helps locate fish by identifying temperature breaks, thermoclines, and thermal fronts where fish commonly congregate.
Professional Installation Requirements
Hull Compatibility Assessment
- Deadrise Angles: 8-15 degrees (12-degree tilt version)
- Hull Materials: Fiberglass, composite, and wood construction
- Installation Method: Thru-hull flush mounting for minimal drag
- Hull Thickness: Compatible with standard recreational boat hull thicknesses
Installation Components Included
- GT12M-THF transducer with 12-degree tilt bronze housing
- Jam nut for secure mounting
- Sealing washer
- Complete installation documentation
- 50-foot marine-grade cable with 8-pin connector
Pre-Installation Considerations
- Verify hull deadrise angle matches transducer tilt specification
- Ensure adequate access from inside hull for installation
- Plan cable routing to compatible Garmin display
- Consider location for optimal sonar performance and boat balance
Garmin Auto-ID Technology
Plug-and-Play Operation
Garmin's advanced auto-identification technology automatically recognizes the GT12M-THF transducer when connected to compatible chartplotters and fishfinders. This eliminates manual configuration and ensures optimal sonar settings from the first power-up.
Automatic Configuration Benefits
- Instant recognition and setup
- Optimized frequency settings
- Proper power level configuration
- Correct depth and temperature calibration
- Eliminates user setup errors
Chartplotter Compatibility
The GT12M-THF is compatible with a wide range of Garmin chartplotters and fishfinders featuring 8-pin transducer connections and CHIRP sonar capability:
Compatible Garmin Units
- ECHOMAP Ultra series
- ECHOMAP UHD series
- GPSMAP series with sonar capability
- Garmin fishfinder combos with CHIRP support
- Units supporting mid-band CHIRP frequencies (85-165 kHz)
- Chartplotters with depth and temperature display capabilities
Professional Installation Tip: Verify your chartplotter's transducer input specifications before installation to ensure full compatibility and optimal performance.
Optimal Marine Applications
Sport Fishing
Exceptional performance for offshore and nearshore angling. Clear baitfish detection, structure identification, and temperature monitoring for productive fishing expeditions.
Tournament Fishing
Competitive advantage with superior target separation and structure definition. Temperature sensing helps locate fish-holding thermoclines and thermal breaks.
Cruising & Navigation
Reliable depth measurement and bottom mapping for safe navigation. Temperature data aids in weather monitoring and route planning decisions.
Commercial Fishing
Professional-grade performance for charter boats and commercial fishing operations requiring dependable fish-finding and navigation capabilities.
Maintenance & Long-Term Performance
Low Maintenance Design
- Bronze housing resists marine corrosion and biofouling
- No moving parts for long-term reliability
- Sealed construction prevents water intrusion
- Marine-grade cable and connections
- Temperature sensor requires no calibration
Preventive Maintenance
- Regular inspection of thru-hull fitting and sealant
- Gentle cleaning of transducer face to remove marine growth
- Annual check of cable connections for corrosion
- Proper winterization procedures in freezing climates
- Periodic verification of depth and temperature accuracy
Frequently Asked Questions
How do I know if the 12-degree tilt is right for my boat?
The 12-degree tilt is designed for boats with hull deadrise angles from 8-15 degrees. Measure your boat's deadrise angle at the transducer location, or consult your boat's specifications. Most sport fishing and cruising boats fall within this range.
What's the difference between this and the 0-degree or 20-degree versions?
The tilt angle must match your boat's hull deadrise for optimal performance. 0-degree is for flat-bottom or low deadrise hulls (0-7°), 12-degree for moderate deadrise (8-15°), and 20-degree for high deadrise hulls (16-24°).
Can this transducer be used in both fresh and salt water?
Yes, the GT12M-THF is designed for both freshwater and saltwater use. Maximum depth performance is 1,200 feet in freshwater and 800 feet in saltwater due to signal attenuation differences.
Does the temperature sensor require calibration?
No, the built-in temperature sensor is factory-calibrated and provides accurate readings without user calibration. It responds quickly to temperature changes for real-time thermal monitoring.
How does CHIRP technology improve fish detection compared to traditional sonar?
CHIRP transmits a continuous sweep of frequencies (85-165 kHz) rather than a single frequency, providing better target separation, clearer fish arches, improved bottom definition, and enhanced ability to distinguish fish from structure.
What installation tools and supplies are needed?
Installation requires a hole saw matching the transducer diameter, drill, marine sealant (5200 or equivalent), basic hand tools, and electrical connections. Professional installation is recommended for optimal results.
Maximize your fishing success with the Garmin GT12M-THF Bronze Thru-Hull Transducer with 12-degree tilt. This precision-engineered transducer delivers professional-grade mid-band CHIRP performance optimized for moderate deadrise hulls, ensuring you have the underwater visibility and temperature data needed for productive fishing and safe navigation.