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Garmin GPSMAP 521/521s Accessories

Garmin accessories for the Garmin GPSMAP 521 and GPSMAP 521s marine chartplotters. All of the GPSMAP 521 accessories available to purchase from ActiveGPS are genuine Garmin parts.

Click the 'More Details' link below for each accessory to read more about it.

Garmin Transducers and BlueChart marine charts are also available for use with the Garmin GPSMAP 521s. For further information please click here or scroll down this page past the GPSMAP 521 accessories below.

This heavy duty cover fits the Garmin GPSMAP 521 or GPSMAP 521s chartplotter head unit snugly, protects screen from getting scratched and guards against the harsh rays of the sun. More Details

Garmin GPSMAP 521/521s Protective Cover - £10.99

For mariners looking for a sleeker installation of the 5-inch screen GPSMAP 521 or GPSMAP 521s at their helm, this flush mount kit is the answer. More Details

Garmin GPSMAP 521/521s Watertight Flush Mount Kit - £24.99

Use the swivel mounting bracket to mount, swivel and tilt your 5-inch Garmin GPSMAP 521 or GPSMAP 521s marine chartplotter to get the best viewing angle. More Details

Garmin GPSMAP 521/521s Swivel Mounting Bracket - £24.99

Add a second mounting station for your 5-inch Garmin GPSMAP 521 or GPSMAP 521s chartplotter on your boat with this second mounting station. The kit also includes a wiring harness to power the GPSMAP 521/521s and ability to connect to an optional NMEA 0183 network, CANet device and transducer. More Details

Garmin GPSMAP 521/521s Second Mounting Station - £34.99

Power or connect your Garmin GPSMAP 521 chartplotter to a network with this power/data cable.

IMPORTANT: This cable is for GPSMAP 521 models WITHOUT a sounder, if you have a GPSMAP 521s model with sounder and require a cable with sounder/transducer connectivity you need to buy the accessory below. More Details

Garmin GPSMAP 521 Power/data Cable - £18.99

Power or connect your Garmin GPSMAP 521s chartplotter to a network with this power/data/xdcr cable. This cable also includes sounder/transducer connectivity.

Please note: This cable is only required if you own the GPSMAP 521s. If you own the GPSMAP 521 without sounder you can purchase the cable above. More Details

Garmin GPSMAP 521s Power/Data/Xdcr Cable - £19.99

Use this genuine Garmin cable to connect your Garmin GPSMAP 521s chartplotter with a 6-pin connection to a single or dual beam transducer with an 8-pin connection. More Details

Garmin GPSMAP 521s 8-pin Transducer to 6-pin Sounder Cable - £16.99

If you are wanting to use your Garmin GPSMAP 521/521s on a boat, you will need this remote marine GA 38 GPS/GLONASS antenna to receive GPS/GLONASS signal. Comes with 10metre (32feet) antenna cable. The kit also includes surface, pole and under-deck (for the underside of fiberglass decks) mounting brackets. More Details

Garmin GPSMAP 521/521s GA 38 GPS/GLONASS Antenna - £49.99

Adding a Transducer to your GPSMAP 521s

Garmin transducers are fully compatible with the Garmin GPSMAP 521s and will provide you with a live 'view' beneath your boat. We stock the very latest Garmin transducers which can provide you with an image of not only what lies directly below but towards the front or sides of your boat with features such as SideVu, DownVu and RealVu 3D Forward.

To learn more about Garmin transducers please see our Garmin Transducer Buyer's Guide, the page also features an online form, which after completing we will email you a link to compatible transducers that are all fully compatible with your Garmin GPSMAP 521s and the boat in which you will use both nautical devices on.

Find your compatible transducer here.

Pictured below, transom mounted transducer, thru-hull transducer and in-hull transducer.

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Adding a Garmin BlueChart to your GPSMAP 521/521s

By adding either a Garmin BlueChart g2 or BlueChart g2 Vision marine chart on SD/microSD Card to your Garmin GPSMAP 521/521s chartplotter will provide the detailed digital marine charts on the screen of your device.

Garmin BlueChart g2/g2 Vision marine charts are available in up to four different sizes, these are: Small, Regular, Large and Extra Large coverage. Please see the sample charts below, which all include Plymouth:

The larger the chart coverage the more area is covered without the need to change or buy additional charts. We suggest buying the chart(s) that provide the coverage for your sailing, fishing or yachting needs.

Charts are available to buy from ActiveGPS for the waters around the UK, Western Europe and Mediterranean coasts. Find your Garmin BlueChart map.

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Why buy from us?

We are official Internet Retailers of Garmin products and we sell genuine Garmin accessories and maps. We purchase from the Garmin UK distributor. We do not buy on the grey market and we do not sell counterfeit products. You can rest assured that by purchasing from ActiveGPS you will receive the full support of Garmin.

Page last updated: 3rd January 2018

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