GARMIN
GPSMAP 421s Chartplotter/Sounder with No Transducer

The GPSMAP 421 is a compact chartplotter that features an ultra-bright 4” (10.16 cm) QVGA color display along with an improved high-speed digital design for increased map drawing and panning speeds. It’s ready to go with a built-in, satellite-enhanced worldwide basemap and an easy-to-use interface designed to help you navigate the open waters with ease. The GPSMAP 421 also accepts BlueChart® g2 Vision® cards for added features and functionality such as high-resolution satellite imagery, 3-D views and Auto Guidance technology.

The GPSMAP 421 basemap contains worldwide satellite images in place of traditional maps. The GPSMAP 421 also comes standard with a high-sensitivity GPS receiver for superior satellite tracking and quicker acquisition times. In addition, the GPSMAP 421 can receive U.S. graphical weather data via optional GXM 51 satellite receiver/antenna. And with an SD™ card slot, it’s easy to add additional maps without connecting to a computer.

Where applicable, the sounder version, GPSMAP 421s, comes with a powerful dual-frequency transducer that clearly illustrates depth contours, fish targets and structures whether you’re fishing in freshwater or off the coast. The GPSMAP 421 and GPSMAP 421s are also NMEA 2000®-certified for easy connectivity with sensors, instruments and future marine offerings.

With the optional BlueChart g2 Vision SD card, you can add a whole new dimension of exceptional features to your chartplotter.

• MarinerEye view and FishEye view provide you a 3-D perspective of map information, both above and below the waterline.
• High-resolution satellite images and aerial photographs help you orient yourself in unfamiliar areas.
• Auto Guidance technology searches through all relevant charts to create a route you can actually follow — one that avoids obstacles, shallow water, buoys and other obstructions.

Physical & Performance:

• Unit dimensions, WxHxD: 5.7" x 5.0" x 2.7" (14.5 x 12.7 x 6.9 cm)
• Display size, WxH: 2.4" x 3.2", 4.0" diagonal (6.1 x 8.1 cm, 10.2 cm diagonal)
• Display resolution, WxH: 240 x 320 pixels
• Display type: QVGA display
• Weight: 1.3 lb (590 g)
• Battery: none
• Battery life: none
• Waterproof: yes (IPX7)
• High-sensitivity receiver: yes
• Antenna: internal
• NMEA input/output: NMEA 0183 compatible and NMEA 2000 certified

Maps & Memory:

• Basemap: yes
• Preloaded maps: no
• Ability to add maps: yes
• Built-in memory: none (cannot load maps to internal memory)
• Accepts data cards: SD™ card slot
• Waypoints/favorites/locations: 3,000
• Routes: 100
• Track log: 10,000 points; 50 saved tracks

Features:

• Garmin radar compatible: no
• Garmin sonar compatible: yes
• Garmin Marine Network™ compatible: no
• Touchscreen: no
• Supports AIS (tracks target ships' position): yes
• Supports DSC (displays position data from DSC capable VHF radio): yes
• Audible alarms: yes
• Tide tables: yes
• Hunt/fish calendar: no
• Sun and moon information: yes
• 3-D map view: yes (with optional BlueChart g2 Vision card)
• Auto Guidance: yes (with optional BlueChart g2 Vision card)
• XM WX Weather & Radio for U.S. & Canada compatible: yes
• Automatic routing (turn by turn routing on roads): no
• Voice prompts (e.g. "Turn right in 500 ft."): no
• Speaks street names (e.g. "Turn right ON ELM STREET in 500 ft."): no
• Headphone jack/audio line-out: no
• Audio/video input/output: no
• Portable: no
• Automotive/motorcycle-friendly: no

What You’ll Need

Transducers, sold separately. Depending on the style of the transducer, you’ll get depth, speed and/or temperature readings. To complete your installation, order one of the following transducers:

Product Specs

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