{"product_id":"garmin-nautical-instrument-gnx-21","title":"Garmin Nautical instrument GNX 21","description":"\u003cp\u003e\u003cstrong\u003eNautical instrument with 4\" inverted LCD screen\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eLarge digits and good readability in white or color on a black background that offer magnificent visibility in conditions without or with poor lighting; choose from 7 customizable backlight colors\u003c\/li\u003e\n\u003cli\u003eScreen with attached glass with anti-reflective lenses that prevents fogging\u003c\/li\u003e\n\u003cli\u003eFully customizable user profiles for navigation with sailing or motor boats that allow you to view the most relevant nautical data and the boat.\u003c\/li\u003e\n\u003cli\u003eLow power consumption (25 mA) with a use of 350 mW (without backlight)\/400 mW (medium level backlight)\u003c\/li\u003e\n\u003cli\u003e5 screen settings and graph and indicator modes to display information related to more than 50 navigation parameters, in addition to depth, speed or wind data\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe easy-to-read inverted screen of the GNX 21 nautical instrument uses white or color digits on a black background to display information related to more than 50 navigation parameters, in addition to depth, speed or wind data. The screen with adhered glass with anti-reflective coating provides excellent readability for both day and night, as well as high-contrast digits that can be enlarged up to 36 mm.\u003c\/p\u003e\n\u003cp\u003eThe GNX 21 device is the first nautical instrument with a screen with attached glass that presents a combination of LCD segments by direct drive and a point matrix field that allows graphic information to be displayed. By consuming little energy (25 mA) with a use of 350 mW (without backlight)\/400 mW (average level of backlight), this device is ideal for sailing boats, as well as a very useful instrument during navigation and fishing activities. Fully customizable user profiles show data related to wind, depth and speed. In addition, the GNX 21 device includes an automatic screen change function that allows you to switch between data screens without user intervention. It can be installed with the low-profile built-in mounting bracket or with the optional flush mounting bracket in order to enjoy the best glass rudder solution and customize your boat as you wish.\u003c\/p\u003e\n\u003ch3\u003eSpecifications:\u003c\/h3\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ch4\u003ePhysical and performance\u003c\/h4\u003e\n\u003c\/div\u003e\n\u003ctable style=\"height: 266px\" width=\"817\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eScreen size (Width\/High)\u003c\/td\u003e\n\u003ctd\u003e83 x 60 mm; 101.6 mm diagonal (3.3” x 2.4”; 4.0” diagonal)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDimensions of the unit (Width\/High\/Depth)\u003c\/td\u003e\n\u003ctd\u003e110 X 115 X 30 mm (4.33\" X 4.53\" X 1.18\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVoltage scale\u003c\/td\u003e\n\u003ctd\u003e9-16 V (from NMEA 2000)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eClassification of water resistance\u003c\/td\u003e\n\u003ctd\u003eIPX7\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWeight\u003c\/td\u003e\n\u003ctd\u003e230 g (8 oz)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAssembly options\u003c\/td\u003e\n\u003ctd\u003eFlat or Flush\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eType of screen\u003c\/td\u003e\n\u003ctd\u003eInverted LCD, monochrome\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\u003cdiv\u003e\n\u003cdiv\u003e\n\u003ch4\u003eCharacteristics\u003c\/h4\u003e\n\u003c\/div\u003e\n\u003ctable\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eCompatible with NMEA 0183\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAutomatic ignition\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTemperature range\u003c\/td\u003e\n\u003ctd\u003eFrom 5° to 158°F (from -15° to 70°C)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eMisc\u003c\/td\u003e\n\u003ctd\u003e\n\u003cul\u003e\n\u003cli\u003eDimensions of the unit (height X width X depth): 11 cm X 11.5 cm X 3 cm\u003c\/li\u003e\n\u003cli\u003eScreen size (diagonal): 10.16 cm (4\")\u003c\/li\u003e\n\u003cli\u003eWeight: 230 g (8 oz)\u003c\/li\u003e\n\u003cli\u003eTemperature range: from -15 °C to 70 °C (from 5 °F to 158 °F)\u003c\/li\u003e\n\u003cli\u003eScreen type\/color: Inverted LCD, monochrome\u003c\/li\u003e\n\u003cli\u003eMaximum digit display size: 36.4 mm\u003c\/li\u003e\n\u003cli\u003eScreen with attached glass: Yes\u003c\/li\u003e\n\u003cli\u003eSeveral color palettes: Yes\u003c\/li\u003e\n\u003cli\u003eCustomizable user profiles for navigation with sailing and motor boats: Yes\u003c\/li\u003e\n\u003cli\u003ePower consumption: 0.35 W (daytime use); 0.4 W (night use)\u003c\/li\u003e\n\u003cli\u003eCompatible with NMEA 2000® and NMEA 0183: Yes\u003c\/li\u003e\n\u003cli\u003eSingle, double and triple display functions: Yes\u003c\/li\u003e\n\u003cli\u003eGraphics: Yes\u003c\/li\u003e\n\u003cli\u003eBrackets for flush\/recess mounting: Yes\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eVitrified screen\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUser profiles\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eNMEA 2000® certified\u003c\/td\u003e\n\u003ctd\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSafety distance of the compass\u003c\/td\u003e\n\u003ctd\u003e209 mm (8.25 in.)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eEnergy consumption\u003c\/td\u003e\n\u003ctd\u003e0.35 W (day); 0.4 W (night)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\u003c!-- sr-faq v=1 vendor=garmin source_sha256=923848c9ffbabb063da467db8b6097939b3a82740474f568b74654dbf74f92e5 --\u003e\u003ch3\u003eFAQs\u003c\/h3\u003e\u003cdetails\u003e\u003csummary\u003eCan I print my own mounting template if I lose the original?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eIt is not recommended to print your own mounting template. The template included in the box should be used to avoid sizing errors during installation.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eHow should unused connectors be protected after installation?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eTo prevent corrosion of the metal contacts, cover unused connectors with the attached weather caps.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eShould marine sealant be used during installation?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eApply marine sealant around the gasket to prevent leakage behind the dashboard.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat is the key safety advice during installation?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eAlways wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhen should I connect all cables to the device during mounting?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eIf you will not have access to the back after mounting, connect all necessary cables before placing it in the cutout.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eIs a fuse required for connecting GNX 21 power?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eThe documentation does not specify a fuse requirement; follow NMEA 2000 network power guidelines.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat additional connections are required for a Garmin HVS GPS antenna?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eIf connecting to a Garmin HVS GPS antenna, specific data cable wires (Black, Yellow, Blue, White) are used as described in the manual.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eHow should the NMEA 2000 power cable be wired for safety?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eConnect the NMEA 2000 power cable to the boat ignition switch or an in-line switch, not directly to the battery to avoid battery drain.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eAre special precautions required when mounting in fiberglass?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eYes, use a countersink bit to drill a clearance counterbore through only the top gel-coat to avoid cracking.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eDoes the included hardware support both flush and flat mounting?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eYes, the included template and hardware can be used to flush mount the device in your dashboard.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat surface should the GNX 21 be mounted on?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eThe mounting surface must be flat and strong enough to support the device and protect it from vibration or shock.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat precautions should I take when drilling or cutting the mounting surface?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eAlways check what is on the opposite side of the surface to avoid damaging the vessel.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eCan the GNX 21 receive NMEA 0183 data and how is it connected?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eThe instrument can receive NMEA 0183 data using an optional data cable (not included), but cannot transmit NMEA 0183 data to NMEA 2000.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eHow should I prepare a fiberglass surface before mounting?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eWhen mounting in fiberglass, use a countersink bit to drill a clearance counterbore through only the top gel-coat layer to avoid cracking when tightening screws.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat type of connector is needed for NMEA 2000 connection?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eThe included NMEA 2000 cables and connectors allow connection to your existing network or creation of a basic one if needed.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cdetails\u003e\u003csummary\u003eWhat are the blue and white wires in the data cable for?\u003c\/summary\u003e\u003cdiv\u003e\u003cp\u003eBlue is Tx\/A (Out+), white is Tx\/B (Out–); both used only when connecting a Garmin HVS GPS antenna.\u003c\/p\u003e\u003c\/div\u003e\u003c\/details\u003e\u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"Can I print my own mounting template if I lose the original?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"It is not recommended to print your own mounting template. The template included in the box should be used to avoid sizing errors during installation.\"}}, {\"@type\": \"Question\", \"name\": \"How should unused connectors be protected after installation?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"To prevent corrosion of the metal contacts, cover unused connectors with the attached weather caps.\"}}, {\"@type\": \"Question\", \"name\": \"Should marine sealant be used during installation?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Apply marine sealant around the gasket to prevent leakage behind the dashboard.\"}}, {\"@type\": \"Question\", \"name\": \"What is the key safety advice during installation?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Always wear safety goggles, ear protection, and a dust mask when drilling, cutting, or sanding.\"}}, {\"@type\": \"Question\", \"name\": \"When should I connect all cables to the device during mounting?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"If you will not have access to the back after mounting, connect all necessary cables before placing it in the cutout.\"}}, {\"@type\": \"Question\", \"name\": \"Is a fuse required for connecting GNX 21 power?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The documentation does not specify a fuse requirement; follow NMEA 2000 network power guidelines.\"}}, {\"@type\": \"Question\", \"name\": \"What additional connections are required for a Garmin HVS GPS antenna?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"If connecting to a Garmin HVS GPS antenna, specific data cable wires (Black, Yellow, Blue, White) are used as described in the manual.\"}}, {\"@type\": \"Question\", \"name\": \"How should the NMEA 2000 power cable be wired for safety?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Connect the NMEA 2000 power cable to the boat ignition switch or an in-line switch, not directly to the battery to avoid battery drain.\"}}, {\"@type\": \"Question\", \"name\": \"Are special precautions required when mounting in fiberglass?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes, use a countersink bit to drill a clearance counterbore through only the top gel-coat to avoid cracking.\"}}, {\"@type\": \"Question\", \"name\": \"Does the included hardware support both flush and flat mounting?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Yes, the included template and hardware can be used to flush mount the device in your dashboard.\"}}, {\"@type\": \"Question\", \"name\": \"What surface should the GNX 21 be mounted on?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The mounting surface must be flat and strong enough to support the device and protect it from vibration or shock.\"}}, {\"@type\": \"Question\", \"name\": \"What precautions should I take when drilling or cutting the mounting surface?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Always check what is on the opposite side of the surface to avoid damaging the vessel.\"}}, {\"@type\": \"Question\", \"name\": \"Can the GNX 21 receive NMEA 0183 data and how is it connected?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The instrument can receive NMEA 0183 data using an optional data cable (not included), but cannot transmit NMEA 0183 data to NMEA 2000.\"}}, {\"@type\": \"Question\", \"name\": \"How should I prepare a fiberglass surface before mounting?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"When mounting in fiberglass, use a countersink bit to drill a clearance counterbore through only the top gel-coat layer to avoid cracking when tightening screws.\"}}, {\"@type\": \"Question\", \"name\": \"What type of connector is needed for NMEA 2000 connection?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The included NMEA 2000 cables and connectors allow connection to your existing network or creation of a basic one if needed.\"}}, {\"@type\": \"Question\", \"name\": \"What are the blue and white wires in the data cable for?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Blue is Tx\/A (Out+), white is Tx\/B (Out–); both used only when connecting a Garmin HVS GPS antenna.\"}}]}\u003c\/script\u003e\u003c!-- \/sr-faq --\u003e","brand":"Garmin","offers":[{"title":"Default Title","offer_id":51626147414353,"sku":"010-01142-10","price":794.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0955\/4434\/4913\/files\/garmin-nautical-instrument-gnx-21-nautical-instrument-gnxtm-21.webp?v=1754729712","url":"https:\/\/www.sailrace.com\/fr-ca\/products\/garmin-nautical-instrument-gnx-21","provider":"SailRACE","version":"1.0","type":"link"}