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GARMIN GNX™ 21 Multifunction Instrument

GARMIN GNX™ 21 Multifunction Instrument

SKU: GAR-100114210

The GNX™ series of marine instruments are the first glass-bonded marine instruments with a combination of directly driven LCD segments and a dot-matrix field to display graphical information. Large, easy-to-read digits and graphs provide high contrast and high visibility.

Their low power consumption is well suited for use on sailboats, and provides valuable instruments for cruising and fishing. Fully customizable user profiles display wind, depth and speed data. Glass-bonded displays with anti-glare lenses avoid fogging.


Displays are either positive format, with dark digits on a white background, or negative format, with light digits on a black background. The GNX Keypad allows ontrol of compatible GNX instrument displays from a distance with a push-button keypad interface which can be fixed-mounted near the helm. 


Key Features

  • Large, easy-to-read white digits and graphs on a black or color background provides high contrast and high visibility
  • Choose from seven customizable backlight colors
  • 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)
  • Five display configurations plus gauge and graph mode to display depth, speed, wind and 50+ marine and boat parameters



  • Display Type: Glass-bonded monochrome LCD, negative background
  • Display Format: Negative
  • Screen Size: 3 5/16"W x 2 3/8"H
  • Functions: More than 50 thru NMEA 2000
  • Dimensions: 4 5/16"W x 4 9/16"H x 1 3/16"D
  • NMEA Interface: NMEA 2000, NMEA 0183 
  • Voltage: 9-16 V (from NMEA 2000) 
  • Weight: 8oz.
  • Waterproof Rating: IPX7 
  • Warranty: One year
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