Tech Specs
In The Box
Transom/trolling mount transducer (dual beam)
6 ft (1.83 m) power/data cable
Bail mounting bracket
Flush mount hardware
Quick start manual
Do you have an old GPS unit lying around? The GPS Nation Trade In and Up program is a great way to trade in your old and used GPS for credit towards a new GPS. The choice is entirely yours! We’ve made the process simple and streamlined. Follow these simple steps, and you will be on your way to receiving credit towards your brand new GPS!
1. Get a quote
To get your free quote, provide your GPS type, manufacturer, model, and condition. Within 24 hours, you will receive a quote for the trade-in value of your current product. The GPS trade-in/trade-up form is at the bottom of this page.
2. Ship your product(s) for trade
After accepting our offer, pack your product(s) safely and ship them to us using the pre-paid shipping label provided to you. We will provide a confirmation email when your trade-in arrives at our warehouse. You have 30 days from the date you complete your on-line trade to ship the product to GPS Nation.
3. Make your purchase
Once we receive your product at our warehouse and we validate the stated condition, we will send you a confirmation email. If you elect to receive credit towards a new GPS at gpsnation.com, your store credit will be issued, and you are free to make your purchase.
Manual & Warranty
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Tech Specs
In The Box
Transom/trolling mount transducer (dual beam)
6 ft (1.83 m) power/data cable
Bail mounting bracket
Flush mount hardware
Quick start manual
Trade-In
Do you have an old GPS unit lying around? The GPS Nation Trade In and Up program is a great way to trade in your old and used GPS for credit towards a new GPS. The choice is entirely yours! We’ve made the process simple and streamlined. Follow these simple steps, and you will be on your way to receiving credit towards your brand new GPS!
1. Get a quote
To get your free quote, provide your GPS type, manufacturer, model, and condition. Within 24 hours, you will receive a quote for the trade-in value of your current product. The GPS trade-in/trade-up form is at the bottom of this page.
2. Ship your product(s) for trade
After accepting our offer, pack your product(s) safely and ship them to us using the pre-paid shipping label provided to you. We will provide a confirmation email when your trade-in arrives at our warehouse. You have 30 days from the date you complete your on-line trade to ship the product to GPS Nation.
3. Make your purchase
Once we receive your product at our warehouse and we validate the stated condition, we will send you a confirmation email. If you elect to receive credit towards a new GPS at gpsnation.com, your store credit will be issued, and you are free to make your purchase.
Manual & Warranty
Overview
Garmin Fishfinder 300C (010-02682-00): Dual Beam Sonar Fishfinder for Freshwater Angling
Introduction
The Garmin Fishfinder 300C delivers real-time sonar imaging specifically engineered for freshwater anglers who need reliable fish detection without complex interfaces. At its core, this unit combines a 3.5" QVGA color display with dual beam sonar technology, allowing you to scan shallow structure and deeper water columns simultaneously. The result is faster target acquisition, fewer blank spots beneath your boat, and measurable improvements in catch success on inland waters.
Key Features
- 3.5" QVGA Color Display with 320 x 240 pixel resolution for clear visibility of underwater structures and fish signatures in sunlight or overcast conditions
- Dual Beam Transducer with selectable 20° narrow beam for precision deep-water readings and 60° wide beam for broader coverage in shallow areas
- 150W RMS / 1,200W Peak-to-Peak power output delivering strong, reliable sonar signals across varying water depths and bottom composition
- Auto Gain Function that automatically adjusts sonar sensitivity in response to changing water conditions, reducing manual tuning requirements
- Ultrascroll® Technology providing rapid screen refresh rates for continuous, real-time monitoring of fish movement and activity
- Round Flasher Mode and Whiteline Feature displaying depth readings with enhanced clarity for precise bottom contact identification
- Built-In Battery Voltage Indicator for real-time power monitoring during extended fishing sessions
- NMEA 0183 Compatibility enabling integration with external GPS units and compatible marine electronics
Data Insights
Performance testing confirms that anglers using high-performance sonar technology like the Fishfinder 300C can increase catch rates by up to 30% through improved fish detection and structure identification. The Ultrascroll® Technology delivers screen updates rapid enough to track live fish activity beneath your vessel, eliminating the delay found in slower sonar units. This continuous refresh rate, combined with the dual beam capability, creates a complete picture of the water column from surface to bottom, giving you actionable intelligence for every fishing scenario.
Usage Instructions
Install the transducer securely below the waterline, ensuring proper water contact for accurate readings. Upon startup, use the dual beam selector to switch between the 20° focused beam for deep exploration and the 60° wide beam for scanning larger areas. Monitor the display continuously during fishing, allowing the auto gain feature to adapt to shifting bottom conditions. Utilize the Round Flasher Mode for precise depth verification when anchoring or working specific structure, and reference the battery voltage indicator to plan for power management on full-day trips.
Design & Material
The Fishfinder 300C balances portability with durability through thoughtful engineering and material selection. Its compact footprint fits easily on center consoles, bow platforms, and gunwale mounts in boats ranging from 16 to 25 feet. The straightforward button layout and logical menu structure allow quick adjustments without screen-fumbling, while the sunlight-readable display eliminates the need for additional hoods or viewing shields.
- Compact Housing measuring approximately 5 x 4 inches, enabling flexible mounting options in tight spaces
- Durable Plastic Casing engineered to resist saltwater splash, UV degradation, and vibration from boat movement
- High-Impact Screen Bezel protecting the display from accidental strikes and mechanical damage
- Weather-Resistant Connector ensuring reliable power and transducer signal transmission in humid freshwater environments
- Lightweight Construction under 2 pounds, reducing installation complexity and allowing easy relocation between boats
- Intuitive Button Interface with dedicated HOME, SELECT, and MENU buttons for one-handed operation while steering or fighting fish
Final Verdict
The Garmin Fishfinder 300C stands as the practical choice for freshwater anglers who want sonar-driven accuracy without the learning curve of advanced systems. Its combination of dual beam technology, powerful 1,200W peak output, and proven 30% catch rate improvement makes it a direct upgrade from traditional fish finders. Whether you fish small lakes, reservoirs, or river systems, the 300C gives you the underwater visibility that separates productive days from frustrating blanks. Equip your boat with this proven performer today and experience the confidence that comes from knowing exactly what's below the surface.




Garmin Warranty