Garmin
GNX™ 21 Marine Instrument
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Warranty Details
Warranty Details


GNX™ 21 Marine Instrument
Marine Instrument with Inverted 4” LCD
- Large, easy-to-read white or color digits on a black background for high visibility in low-light or darkness; choose from 7 customizable backlight colors¹
- Glass-bonded display with anti-glare lens avoids fogging
- Fully customizable user profiles for sail or power boating to display most important marine and vessel data
- Low power consumption (25 mA) with 350 mW (no backlight)/400 mW (mid-level backlight)
- 5 display configurations plus gauge and graph mode to display depth, speed, wind and 50+ marine and boat parameters
The easy-to-read GNX 21 marine instrument has an inverted display with white or color digits on a black background that clearly shows depth, speed, wind and 50-plus marine and boat parameters. Its glass-bonded display with anti-glare lens coating provides excellent daytime and nighttime readability with high-contrast digits scalable up to 36 mm.
The GNX 21 is the first glass-bonded marine instrument with a combination of directly driven LCD segments and a dot-matrix field to display graphical information. Its low power consumption — (25 mA) with 350 mW (no backlight)/400 mW (mid-level backlight) — is perfect for use on sailboats, and provides a valuable instrument for cruising and fishing. Fully customizable user profiles display wind, depth and speed data. Plus, the GNX 21 includes an auto-scroll feature that rotates through data screens for hands-free operation. It can be installed with the included low profile flush mount or an optional flat mount for the ultimate glass helm solution and custom look for your boat.
specs:
General |
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Dimension | 110 x 115 x 30 mm (4.33" x 4.53" x 1.18") |
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Weight | 230 g (8 oz) |
Water rating | IPX7 |
Display Type | Inverted LCD, monochrome |
Display Size |
83 x 60 mm; 101.6 mm diagonal (3.3” x 2.4”; 4.0” diagonal) |
Mounting Options | Flat or Flush |
Glass bonded display | |
Temperature range | From 5° to 158°F (from -15° to 70°C) |
Sensors |
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NMEA 0183 Compatible |
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Electrical Features |
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Power Consumption |
0.35 W (day); 0.4 W (night) |
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Compass-safe distance | 209 mm (8.25 in.) |
Instrument Features |
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Auto-on | |
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User profiles |
in the box:
- GNX 21
- Trim piece snap cover
- Protective cover
- Flush mount gasket and hardware
- NMEA 2000® T-connector
- NMEA 2000 drop cable
- Installation instructions
- Documentation
features:
Easy-to-read Display
Unique high-contrast hybrid display features large, easy-to-read digits scalable up to 36 mm tall. Offers excellent clarity in direct sunlight, at dusk, or at night. The dot-matrix section can show additional details and/or graphical information.
Glass-bonded Display
Glass-bonded display helps prevent fogging, and the anti-glare lens finish increases visibility.

Customizable Color Background
Choose from 7 different backlight colors, or even create a customized color, to achieve the screen that provides optimum readability for you.

Customizable User Profiles
Fully customizable user profiles allow you to choose from 5 available display configurations for sailboat or powerboat user-profiles: single, dual and triple function, plus gauge and graph mode to display wind, depth and speed data, or customize the pages to display the marine and boat data that is most important to you.

Auto Scroll
Set your display to automatically cycle between pages at a speed you set for convenient, hands-free operation.

Low Power Consumption
Perfect for sailors who want to sail for long intervals without having to run a motor or generator to charge batteries. The GNX 20 uses only 25 mA with 350 mW daytime usage, requiring no backlight and just 400 mW with a mid-level backlight setting at night.

NMEA® 2000
Monitor more than 50 marine and boat parameters, including GPS speed, water depth and temperature, wind direction, and wind speed from the NMEA 2000 bus. You can also add a NMEA 0183 device using the optional 7-pin bare-wire power/data cable.

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Passion
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Who We Are
With 15 years in the marine industry, and 10 years running our own company, we know batteries and what you’ll need for your goals. With us, you’ll get quality and good value for your money. Our aim is to always deliver on our promises, and never promise more than we can. We’ll tell you the truth, whether it goes above or below your budget. Learn more about Thomas and MarineBatteryCo. here.
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