Garmin GNX 21 Marine Instrument with Inverted Monochrome LCD 4 inch

Manufacturer Part No: 010-01142-10 | ID: 156107 | £266.63 ex-VAT
Price Checked √ - Free UK Delivery √

The easy-to-read GNX 21 marine instrument has an inverted display with white or colour 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 customisable 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.

Garmin GNX 21 Marine Instrument with Standard Monochrome LCD 4 inch

The easy-to-read GNX 21 marine instrument has an inverted display with white or colour 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.


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.


Customisable Colour Background

Choose from 7 different backlight colours, or even create a customised colour, to achieve the screen that provides optimum readability for you.


Customisable User Profiles

Fully customisable 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 customise 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 21 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.

Garmin Flush Mount Gasket GMI 10

Flush mount your GMI 10 / GHC 10 with this flush mount gasket.


ID: 144416 | £11.67 ex-VAT

Garmin Top and Bottom Snap Covers for the GHC 10 and GMI 10 Displays

Protect your GMI 10 with these top and bottom snap covers.


ID: 144415 | £11.67 ex-VAT

Garmin GND 10 Black Box Bridge between gWind and NMEA2000

The GND 10 black box bridge seamlessly integrates Nexus instruments and sensors with the Garmin family. It converts data between the Nexus Network and NMEA2000 to provide compatibility between Nexus and Garmin products, including gWind, gWind Wireless and gWind Race transducers. Simple plug-and-p...


ID: 155882 | £108.29 ex-VAT

Garmin gWind NiMH Battery Replacement

The internal batteries of the gWind Wireless are continuously charged by a small solar panel integrated on the transducer arm, and have a life of around 3 to 4 years. But when the time comes to replace them, they can be easily replaced with this NiMH battery.


ID: 156485 | £22.50 ex-VAT

Garmin Nexus Cable with Bare Ends 8m

Extend your Nexus Network in your boat with this 8 m cable with bare ends.


ID: 156488 | £14.17 ex-VAT

Garmin gWind Propeller

Don’t let a missing propeller keep you from receiving accurate wind data. Our replacement propeller ensures you can maintain the twin-fin technology with 3-bladed propeller our gWind family of transducers are known for in the marine market.


ID: 156484 | £14.17 ex-VAT

Garmin gWind Race Mast Bracket

Secure your gWind Race mast securely with this bracket.


ID: 156483 | £60.00 ex-VAT

Garmin gWind Mast Bracket

Secure your gWind and gWind Wireless mast securely with this bracket.


ID: 156482 | £11.67 ex-VAT

Garmin gWind Mast Cable (40m)

Run this 25 m (82 ft) cable up the mast to connect your gWind and gWind Race transducers.


ID: 156490 | £75.00 ex-VAT

Garmin Replacement Wind Cups for the GWS 10 Wind Transducer Anomometer

Garmin Replacement Wind Cups for the GWS 10 Wind Transducer Anomometer


ID: 148967 | £33.33 ex-VAT

Garmin Replacement Wind Wane for the GWS 10 Wind Transducer

Determine wind direction with your GWS™ 10 with this wind vane.


ID: 148968 | £33.33 ex-VAT

Garmin Replacement Core for the GWS 10 Wind Transducer

Replace the section between the anemometer and the wind vane on your GWS 10 with this core replacement.


ID: 148969 | £295.83 ex-VAT

Garmin 7 Pin Power Cable GMI 10

Price Checked √ - Free UK Delivery √

Use the bare wires on this power/data cable to hard wire your compatible device.


ID: 144417 | £16.67 ex-VAT

USB Mini-B Cable for GND 10

Connect your GND 10 black box bridge to your computer with this USB mini-B cable — so it can send sailing-specific functions via the Nexus FDX protocol to the Nexus and NMEA 2000® networks.


ID: 156487 | £11.54 ex-VAT

Garmin gWind Mast cable 25m

Run the 25 m (82 ft) cable up the mast to connect your gWind™ and gWind Race transducers.


ID: 156491 | £47.50 ex-VAT

Garmin GHC 10 GMI 10 protective cover

Garmin GHC 10 GMI 10 protective cover.


ID: 144414 | £11.67 ex-VAT

Garmin Mounting Kit GST 43

Replace your transducer housing without having to replace the entire transducer with this mounting kit. It includes the thru-hull fitting, nut, o-ring, locking spring and dummy unit. Make sure to follow the directions so you don’t damage your boat.


ID: 157871 | £15.83 ex-VAT

Garmin Paddle Wheel GST 43

Replace your paddle wheel without having to replace the entire transducer. This kit includes the paddle wheel and the paddle wheel shaft.


ID: 157870 | £19.17 ex-VAT

Garmin 8-pin Female to wire block adapter

This adapter allows you to connect the wires on legacy 6-pin transducers with newer sonar that require a 8-pin connection.


ID: 151715 | £48.33 ex-VAT

Garmin NMEA0183 Power and Data Cable for Intelliducers and GPS 17x

Use our NMEA 0183 power cable to provide power to your NMEA 0183 network. Connects to the network with an 8-pin female connector.


ID: 144428 | £31.67 ex-VAT

Garmin Nexus Network Cable with Straight Connectors 5m

Use our 5 m straight cable to connect your GND 10 to the Nexus network so you can get sailing-specific functions.


ID: 156486 | £26.67 ex-VAT

Garmin gWind to nWind Connector Adapter Cable

Use our connector adapter cable to retrofit your gWind transducer for the Nexus network using your existing Nexus mast cable.


ID: 156492 | £20.83 ex-VAT

Garmin Trim Snap Piece Cover Bezel for the GNX 120 Display

Don’t let misplaced or broken trim blemish the beauty of your Garmin GNX 120.


ID: 156658 | £10.00 ex-VAT

Garmin Protective Sun Cover for the GNX 130

Our protective cover fits your Garmin GNX 130, keeping it safe from the harsh marine environment when not in use.


ID: 156657 | £12.92 ex-VAT

Garmin Protective Sun Cover for the GNX 120

Our protective cover fits your Garmin GNX 120, keeping it safe from the harsh marine environment when not in use.


ID: 156656 | £14.17 ex-VAT

Garmin Mast bracket protective cover for 4 GNX120 Displays

Protect the GNX 120 displays mounted on the mast with this cover. Saves losing individual suncovers.


ID: 156655 | £54.17 ex-VAT

Garmin Mast bracket protective cover for 3 GNX120 Displays

Protect the GNX 120 displays mounted on the mast with this cover. Saves losing individual suncovers.


ID: 156654 | £42.50 ex-VAT

Garmin Mast bracket protective cover for 2 GNX120 Displays

Protect the GNX 120 displays mounted on the mast with this cover. Saves losing individual suncovers.


ID: 156653 | £30.00 ex-VAT

Garmin Carbon Fibre mast brackets for 4 GNX120 Displays

Mount 4 GNX 120 instrument displays to the mast with this carbon fiber bracket. It offers a sleek, compelling industrial design, providing a glass mast look.


ID: 157845 | £415.83 ex-VAT

Garmin Carbon Fibre mast brackets for 3 GNX120 Displays

Mount 3 GNX 120 instrument displays to the mast with this carbon fiber bracket. It offers a sleek, compelling industrial design, providing a glass mast look.


ID: 157844 | £340.28 ex-VAT

Garmin Trim Snap Piece Cover Bezel for the GNX 130 Display

Don’t let misplaced or broken trim blemish the beauty of your Garmin GNX 130.


ID: 156659 | £10.00 ex-VAT

Garmin Trim Snap Piece Cover Bezel for the GNX Keypad

Don’t let misplaced or broken trim blemish the beauty of your Garmin GNX Keypad


ID: 156660 | £9.17 ex-VAT

Garmin Flush Mount Gasket for the GNX 120 Display

Our flush mount gasket allows you to easily position your GNX 120 against most flat surfaces in your boat.


ID: 156661 | £12.92 ex-VAT

Garmin Nexus Field Installable Connectors, M8 M/F

Use our water resistant male/female field-installable connectors at the foot of the mast for easy connection of the mast cables on our gWind™ family of transducers when stepping the mast.


ID: 156489 | £54.17 ex-VAT

Garmin 7-Pin Power Data Cable With 90 Degree Connector for GMI 20 and GHC 20

Connect your GMI 20 or GHC 20 to a NMEA0183 device with this 7-pin power/data cable. Features 90-degree connector for installation in tight spaces or flush mounting.


ID: 156108 | £19.17 ex-VAT

Garmin Silver and Black Trim Snap Piece Cover Bezel for GMI GNX and GHC 4 inch Displays

Don’t let a lost or broken trim piece blemish the beauty of your helm. Use our replacement trim bezel and mount your GMI 20 digital marine instrument display or GHC 20 marine autopilot control unit. Or, simply use the trim piece to help match the GMI/GHC to the GPSMAP 8000 Glass Helm series...


ID: 155328 | £9.42 ex-VAT

Garmin Black Trim Snap Piece Cover Bezel for GMI GNX and GHC 4 inch Displays

Don’t let a lost or broken trim piece blemish the beauty of your helm. Use our replacement trim bezel and mount your GMI 20 digital marine instrument display or GHC 20 marine autopilot control unit. Or, simply use the trim piece to help match the GMI/GHC to the GPSMAP 8000 Glass Helm series...


ID: 155327 | £7.08 ex-VAT

Garmin Flush Mount Gasket for GMI GNX and GHC 4 inch Displays

Flush or flat mount your GMI 20 digital marine instrument display or GHC 20 marine autopilot control unit with this flush-mount gasket.


ID: 155326 | £4.33 ex-VAT

Garmin Protective Sun Cover for GMI GNX and GHC 4 inch Displays

Use our protective cover to protect your device from the harsh marine environment when not in use.


ID: 155325 | £7.08 ex-VAT

Garmin Flat Mount Kit for GMI GNX and GHC 4 inch Displays

Mount your GMI 20 digital instrument display or GHC 20 marine autopilot control unit into a flat panel, giving your boat a beautiful, sleek glass helm. Includes hardware, installation instructions and a template. This type of mounting requires full access to the back of the mounting surface, and...


ID: 155324 | £20.83 ex-VAT

Garmin Flush Mount Gasket for the GNX 130 Display

Our flush mount gasket allows you to easily position your GNX 130 against most flat surfaces in your boat.


ID: 156662 | £13.33 ex-VAT

Garmin Carbon Fibre mast brackets for 2 GNX120 Displays

Mount 2 GNX 120 instrument displays to the mast with this carbon fiber bracket. It offers a sleek, compelling industrial design, providing a glass mast look.


ID: 157843 | £277.78 ex-VAT
  • GNX 21
  • Trim piece snap cover
  • Protective cover
  • Flush mount gasket and hardware
  • NMEA 2000 drop cable
  • NMEA 2000 T-connector
  • Installation instructions
  • Documentation

Garmin GNX 20 Marine Instrument with Standard Monochrome LCD 4 inch

Price Checked √ - Free UK Delivery √

The easy-to-read GNX 20 marine instrument display with black digits on a white or colour background 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-contras...


ID: 156106 | £266.63 ex-VAT

Garmin GNX 21 Marine Instrument with Inverted Monochrome LCD 4 inch

Price Checked √ - Free UK Delivery √

The easy-to-read GNX 21 marine instrument has an inverted display with white or colour 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 readabil...


ID: 156107 | £266.63 ex-VAT

Garmin GNX Wind Marine Instrument LCD 4 inch

Price Checked √ - Free UK Delivery √

The GNX Wind features a high-visibility, glass-bonded backlit monochrome LCD display with customisable backlight colours making it easy to see from nearly any angle and even at a distance. Background colours can be customised to nearly any colour preference to provide the contrast and visibility...


ID: 157705 | £345.78 ex-VAT

Garmin GMI 20 Marine Instrument Display with Colour LCD 4 inch

Price Checked √ - Free UK Delivery √

Perfectly Designed for Power and Sail Vessels

Designed to clearly show depth, speed, wind and 100+ marine and vessel parameters, its large, bright 4″ colour display with extra large digits is easy to read at a distance and has a 170 degree viewing angle. A glass-bonded lens preven...


ID: 155244 | £354.16 ex-VAT

Garmin gWind Mast Head Transducer with GND10 Black Box and 25m mast cable

The gWind transducer features twin-fin technology with 3-bladed propeller for accurate TWS in lighter air while the twin-fin design gives a stable TWA. The 3-bladed propeller, unlike a cups design, is always efficient. Combined with optic reading this transducer provides superior accuracy at low...


ID: 155879 | £361.11 ex-VAT

Garmin gWind Race Vertical Mast Head Transducer with GND10 Black Box and 25m mast cable

Price Checked √ - Free UK Delivery √ On Offer

Designed for racing sailboats, the gWind Race features a 1 meter straight pole to raise the transducer above the mast to remove turbulence errors. Features twin-fin technology with 3-bladed propeller for more accurate TWS in lighter air while the twin-fin design gives a more stable TWA. The 3-bla...


ID: 155881 | £821.67 ex-VAT

Garmin gWind Wireless Wind Pack with GND10 WSI Box and Transducer

The gWind™ Wireless transducer offers an easy-to-install solution that eliminates running wires down the mast. Dedicated radio signals are sent through the included WSI connection box and GND 10 black box bridge that allows shared communication of critical NMEA 2000 data between the Nexus N...


ID: 155880 | £421.67 ex-VAT

Garmin gWind Transducer Only

Garmin gWind™ sensors feature a 3-bladed propeller and twin-fin design for more accurate True Wind Speed (TWS) in lighter air and more stable True Wind Angle (TWA). Garmin offers a wide selection of wind sensors designed for both sail and power vessels. Some are specialised for sailing and...


ID: 157933 | £258.33 ex-VAT

Garmin gWind Transducer with Nexus Adapter

This bundle can be used by existing Nexus customers who are looking to replace their nWind transducer with a Garmin gWind series transducer. Using the nWind to gWind connector adapter cable, customers can retrofit the included gWind transducer to an existing Nexus network using an existing Nexus...


ID: 157513 | £312.49 ex-VAT

Garmin gWind Wireless Transducer Only

Now Garmin chartplotter owners can enjoy the advantages of Nexus sail equipment and vice versa. The gWind Wireless transducer features renowned Nexus twin-fin technology with 3-bladed propeller, providing more accurate TWS in lighter air and more stable TWA. Optic reading provides superior accura...


ID: 157935 | £316.67 ex-VAT

Garmin gWind Race Transducer Only

Designed for racing sailboats, the gWind Race features a 1 meter straight pole to raise the transducer above the mast to remove turbulence errors. Features twin-fin technology with 3-bladed propeller for more accurate TWS in lighter air while the twin-fin design gives a more stable TWA. The 3-bla...


ID: 157934 | £670.83 ex-VAT

Garmin gWind Race Transducer with Nexus Adapter

This bundle can be used by existing Nexus customers who are looking to replace their nWind transducer with a Garmin gWind series transducer. Using the nWind to gWind connector adapter cable, customers can retrofit the included gWind Race transducer to an existing Nexus network using an existing N...


ID: 157928 | £683.33 ex-VAT

Garmin GST 43 Analogue Thru Hull Speed Transducer

The GST 43 is a thru-hull transducer that can read water speed and temperature. The transducer can retrofit an existing Nexus 43mm thru-hull transducer (TH43). This is connected to the GST 10 which converts to NMEA 2000 so the information can be displayed on a compatible Garmin chartplotter or in...


ID: 157758 | £95.00 ex-VAT

Garmin GST 43 and GST 10 Bundle Analogue Thru Hull Speed Transducer and NMEA2000 Converter Bundle

The GST 43 is a thru-hull transducer that can read water speed and temperature. The transducer can retrofit an existing Nexus 43mm thru-hull transducer (TH43). Bundled with the GST 10, the GST 43 can connect directly to the NMEA 2000 network, and the information can be displayed on a compatible G...


ID: 157759 | £109.17 ex-VAT

Garmin Airmar ST850 Speed Temp Sensor Plastic Thru-hull 8 pin

Easily collect your vessel speed and the water temperature with our speed/temperature sensor. This plastic thru-hull mount sensor uses a paddle wheel to determine vessel speed while the temperature sensor indicates the current water temperature. Speed and temperature information is collected and...


ID: 151713 | £116.66 ex-VAT

Garmin New Echo Series Speed Sensor

Easily collect speed data and send it to your echo fishfinder with our water sensor. Simply mount our speed sensor on the transom of your vessel and connect it to your device. The paddle wheel on the speed sensor turns as the vessel moves through the water, and speed data is collected and display...


ID: 151682 | £43.33 ex-VAT

Garmin Airmar T80 Water Temperature probe Stainless steel Transom mount 8 pin

Find out the water surface temperature by attaching our 8-pin stainless steel temperature probe to your transducer.


ID: 151714 | £85.00 ex-VAT

Garmin GDT 43 Analogue Thru Hull Depth and Temperature Transducer

This thru-hull transducer can read water depth and water temperature. It can retrofit an existing Nexus and Silva 43 mm thru-hull transducer (TH43). When bundled with the NMEA 2000 adapter, the GDT 43 can connect directly to the NMEA 2000 network, and the information can be displayed on a compati...


ID: 158038 | £95.83 ex-VAT

Garmin GDT 43 Analogue Thru Hull Depth and Temperature Transducer and NMEA2000 Converter Bundle

This thru-hull transducer can read water depth and water temperature. It can retrofit an existing Nexus and Silva 43 mm thru-hull transducer (TH43). When bundled with the NMEA 2000 adapter, the GDT 43 can connect directly to the NMEA 2000 network, and the information can be displayed on a compati...


ID: 158039 | £185.00 ex-VAT