Please note: This product does not include a transducer. We offers a complete selection of transducers that you can purchase separately as accessories.

Features

Use a serial cable to connect this black-box sounder directly to your chartplotter
for a superb sonar experience. Once you connect your GSD 21 to your chartplotter with
CANnet, Garmin’s 1 MB proprietary network, you can use UltraScroll to provide
ultra-fast refresh rates.

The GSD 21 is a high-dynamic range sounder that performs exceptionally up to 1,500
feet. You can connect it to a dual-frequency transducer (50/200 kHz) for amazing
deep-water performance, and 500 watts of transmit power, or connect it to a
dual-beamwidth transducer for use in both shallow freshwater and deep water, along
with a transmit power of 400 watts.

Specifications

Other Products in the Series:

	GARMIN GCV 10 SideVu DownVu CHIRP Scanning Sonar	Add to comparison
	GARMIN GCV 10 SideVu DownVu CHIRP Scanning Sonar, no Transducer	Add to comparison
	GARMIN GSD 20 Remote Sounder NOH
	GARMIN GSD 21 Analog Sonar NOH
	GARMIN GSD 22 Digital Sonar NOH
	GARMIN GSD 22 Digital Sonar	Add to comparison
	GARMIN GSD 24 Digital Sonar	Add to comparison
	GARMIN GSD 25 Premium Sonar Module	Add to comparison
	GARMIN GSD 26 Digital Sonar	Add to comparison

Also available:

GARMIN GCV 10 SideVu DownVu CHIRP Scanning Sonar

010-01156-02
$536.95
GCV 10 SideVu DownVu CHIRP Sca

GARMIN GCV 10 SideVu DownVu CHIRP Scanning Sonar, no Transducer

010-01156-10
$338.95
GCV 10 SideVu DownVu CHIRP Sca

010-00957-00
$586.95
GSD 24 Digital Sonar

010-01159-00
$751.95
GSD 25 Premium Sonar Module

010-00958-00
$1,658.95
GSD 26 Digital Sonar

Accessories:

Adapters Chargers

010-10253-00
$7.95
Suction cup transducer adapter

Out of stock

GARMIN Trolling motor transducer adapter

010-10251-00
$6.95
Trolling motor transducer adap

Out of stock

Cables

GARMIN 20 ft. Extension cable for transducers, with ID

010-10716-00
$68.95
20 ft. Extension cable for tra

GARMIN 10 ft. Extension cable for transducers, ID

010-10715-00
$67.95
10 ft. Extension cable for tra

NMEA 2000

010-11525-00
$134.95
NMEA 2000 Transducer Adapter K

Sensors and Boards

010-10279-01
$70.95
Speed Sensor

010-10225-00
$49.95
Temperature probe

Out of stock

Transducers Garmin 4/12/18-pin (Transducer Guide)

GARMIN P66 Transducer transom or trolling motor mount, dual beam 4-pin

010-10249-20
$65.95
P66 Transducer transom or trol

Transducers Garmin 6-pin In-hull (Transducer Guide)

Garmin M260-6G 1kW 200/50KHz Transducer In hull 6 pin f GSD22

010-10641-00
$775.95
M260-6G 1kW 200/50KHz Transduc

GARMIN M260-6BR 1kW 200/50KHz 6/19deg mounting tank transducer

010-10445-00
$819.95
M260-6BR 1kW 200/50KHz 6/19deg

GARMIN P79-6G 200/50KHz 12/45deg plastic adjustable Transducer

010-10327-00
$122.95
P79-6G 200/50KHz 12/45deg plas

010-10224-00
$56.95
P72 200KHz plastic Transducer

Out of stock

GARMIN R199-6BR 2kW 200/50 Khz Transducer

010-10643-00
$2,270.95
R199-6BR 2kW 200/50 Khz Transd

Transducers Garmin 6-pin Thru-hull (Transducer Guide)

Garmin B164 1kW 0 tilt 200/50kHz bronze, Transducer 6 pin

010-11010-03
$833.95
B164 1kW 0 tilt 200/50kHz bron

GARMIN B117 0-8 tilt 50/200 kHz Bronze Transducer 6 pin

010-10182-01
$189.95
B117 0-8 tilt 50/200 kHz Bronz

GARMIN B117 0-8 tilt 50/200 kHz 12/45deg bronze Transducer, depth

010-10182-00
$172.95
B117 0-8 tilt 50/200 kHz 12/45

Out of stock

GARMIN B164 1kW 20 tilt 50/200 kHz bronze Transducer 6 pin

010-11010-00
$833.95
B164 1kW 20 tilt 50/200 kHz br

GARMIN B164 1kW 12 tilt 200/50kHz Bronze Transducer 6pin

010-11010-01
$833.95
B164 1kW 12 tilt 200/50kHz Bro

GARMIN B22 200KHz 12deg bronze Transducer

010-10107-00
$125.25
B22 200KHz 12deg bronze Transd

Out of stock

GARMIN B22 12 tilt 200KHZ Bronze Transducer

010-10217-00
$159.95
B22 12 tilt 200KHZ Bronze Tran

GARMIN B258-6g 1kW 50/200 kHz thru-hull 6 pin transducer

010-10703-00
$625.99
B258-6g 1kW 50/200 kHz thru-hu

GARMIN B260-6BR 1KW 200/50KHz 6/19deg bronze Transducer

010-10451-00
$819.95
B260-6BR 1KW 200/50KHz 6/19deg

GARMIN B260-6BR DT Cone 19/6 1kW 200/50KHz Bronze 6pin Transducer

010-10640-00
$845.95
B260-6BR DT Cone 19/6 1kW 200/

Garmin B45-DT-6G Thru-Hull 50/200 kHz Bronz Narrow Stem 6pin Transducer

010-10983-00
$199.95
B45-DT-6G Thru-Hull 50/200 kHz

GARMIN B60-12-6g 12 Tilt 50/200 kHz Transducer

010-10982-01
$226.95
B60-12-6g 12 Tilt 50/200 kHz T

GARMIN B60-20-6g 20 Tilt 50/200 kHz Transducer

010-10982-00
$226.95
B60-20-6g 20 Tilt 50/200 kHz T

GARMIN B744V-6G DTS 50 200 khz 600 w Bronze Thru Hull Transducer

010-10183-02
$293.95
B744V-6G DTS 50 200 khz 600 w

GARMIN B744VL-6G Long STEM DTS 50 200 khz 600 w Bronze Thru Hull Transducer

010-10193-02
$386.95
B744VL-6G Long STEM DTS 50 200

010-10119-00
$79.95
P19 200kHz 12Deg Transducer

Out of stock

GARMIN P319-6G Nylon 0-8 tilt 50/200 kHz Plastic Transducer

010-10194-01
$143.95
P319-6G Nylon 0-8 tilt 50/200

GARMIN P319 0-8 tilt 50/200 kHz plastic Transducer, depth only

010-10194-00
$142.95
P319 0-8 tilt 50/200 kHz plast

Out of stock

Airmar For Garmin SS164 0 tilt 200/50 kHz 1 Kw Steel 6pin Transducer

SS164-0-6G
$794.95
For Garmin SS164 0 tilt 200/50

Airmar For Garmin SS164 12 tilt 200/50 kHz 1Kw 6pin steel Transducer

SS164-12-6G
$794.95
For Garmin SS164 12 tilt 200/5

Airmar For Garmin SS164 20 tilt 200/50 kHz 1 Kw Steel 6pin Transducer

SS164-20-6G
$794.95
For Garmin SS164 20 tilt 200/5

Airmar For Garmin SS260 HD DT Cone 19/6 1kW 200/50KHz Steel 6pin Transducer

SS260-6BR
$1,028.95
For Garmin SS260 HD DT Cone 19

GARMIN SS270W-6G 1kW 200/50kHz,Cone 25, Thru-Hull,6pin Transducer

010-11140-00
$1,493.95
SS270W-6G 1kW 200/50kHz,Cone 2

Airmar For Garmin SS60 0 deg tilt 50/200 kHz 600W 6pin Transducer

SS60-0-6G
$374.95
For Garmin SS60 0 deg tilt 50/

Airmar For Garmin SS60 12 deg tilt 50/200 kHz 600W 6pin Transducer

SS60-12-6G
$374.95
For Garmin SS60 12 deg tilt 50

Airmar For Garmin SS60 20 deg tilt 50/200 kHz 600W 6pin Transducer

SS60-20-6G
$374.95
For Garmin SS60 20 deg tilt 50

Transducers Garmin 6-pin Transom (Transducer Guide)

GARMIN P66 200/50KHz 10/40deg Transducer

010-10272-00
$74.95
P66 200/50KHz 10/40deg Transdu

GARMIN P66 200KHz 45/15 degrs dual beam transducer

010-10249-00
$49.95
P66 200KHz 45/15 degrs dual be

Discontinued

Airmar For Garmin Cone 19/6 1kW 50/200KHz 6pin Tank-Mount Transducer

CM260-6BR
$830.95
For Garmin Cone 19/6 1kW 50/20

Airmar For Garmin Beam 25 1kW 50/200KHz 6pin Tank-Mount Wide-Beam Transducer

CM270W-6G
$995.95
For Garmin Beam 25 1kW 50/200K

GARMIN P66 200/50KHz 12/45deg plastic Transducer

010-10192-01
$121.95
P66 200/50KHz 12/45deg plastic

GARMIN P23 20deg 200KHz Transom-Mount Plastic 6pin Transducer

010-10105-00
$49.95
P23 20deg 200KHz Transom-Mount

Out of stock

Airmar For Garmin TM258-6G DT Cone 3-21 1kW 200/50kHz Transom 6pin Transducer

TM258-6G
$560.95
For Garmin TM258-6G DT Cone 3-

Transducers Garmin 8-pin/bare wires In-hull (Transducer Guide)

GARMIN M260-8G 1kW 200/50kHz In-Hull Plastic Transducer

010-10641-20
$833.95
M260-8G 1kW 200/50kHz In-Hull

GARMIN P79-8G 200/50kHz Plastic Adjustable Transducer

010-10327-20
$142.95
P79-8G 200/50kHz Plastic Adjus

GARMIN R199-8G 2kW 200/50kHz plastic Transducer

010-10643-20
$2,399.95
R199-8G 2kW 200/50kHz plastic

Transducers Garmin 8-pin/bare wires Thru-hull (Transducer Guide)

010-10182-21
$215.95
B117 200/50kHz Bronze Transduc

GARMIN B164 1kW 20 tilt 200/50kHz Bronze Tilted Transducer 8 pin

010-11010-20
$833.95
B164 1kW 20 tilt 200/50kHz Bro

GARMIN B164 1kW 12 tilt 200/50kHz Bronze Tilted Transducer 8pin

010-11010-21
$823.95
B164 1kW 12 tilt 200/50kHz Bro

Garmin B164 1kW 0 tilt 200/50kHz Bronze Transducer 8-pin

010-11010-22
$888.95
B164 1kW 0 tilt 200/50kHz Bron

GARMIN B258 1kW 200/50kHz Bronze Transducer 8-pin

010-10703-20
$655.95
B258 1kW 200/50kHz Bronze Tran

Garmin B260-8G DT Cone 19/6 1kW 200/50KHz Bronze 8pin Transducer

010-10640-20
$1,009.95
B260-8G DT Cone 19/6 1kW 200/5

GARMIN B45-DT-8G Thru-Hull 50/200 kHz Bronz Narrow Stem 8pin Transducer

010-10983-20
$199.95
B45-DT-8G Thru-Hull 50/200 kHz

GARMIN B60-12-8g 12 deg tilt 200/50kHz Bronze Transducer

010-10982-21
$239.95
B60-12-8g 12 deg tilt 200/50kH

GARMIN B60-20-8g 20 deg tilt 200/50kHz Bronze Transducer

010-10982-20
$256.95
B60-20-8g 20 deg tilt 200/50kH

GARMIN B619 12 deg tilt 77/200 kHz Transducer

010-10217-21
$170.95
B619 12 deg tilt 77/200 kHz Tr

GARMIN B619 20 deg tilt 77/200 kHz Transducer

010-10217-22
$170.95
B619 20 deg tilt 77/200 kHz Tr

GARMIN B744V-8G DTS 50 200 khz 600 w Bronze Thru Hull Transducer

010-10183-22
$338.95
B744V-8G DTS 50 200 khz 600 w

GARMIN B744VL-8G Long STEM DTS 50 200 khz 600 w Bronze Thru Hull Transducer

010-10193-22
$421.95
B744VL-8G Long STEM DTS 50 200

GARMIN P72-8G 500W 77/200 kHz Transducer

010-10200-20
$84.95
P72-8G 500W 77/200 kHz Transdu

GARMIN P19 12 deg tilt 77/200 kHz Transducer

010-10218-21
$125.95
P19 12 deg tilt 77/200 kHz Tra

GARMIN P319-8G 200/50kHz Plastic Transducer 8 pin

010-10194-21
$125.95
P319-8G 200/50kHz Plastic Tran

GARMIN P19 20 deg tilt 77/200 kHz Transducer

010-10218-22
$125.95
P19 20 deg tilt 77/200 kHz Tra

GARMIN SS164 0 deg tilt 1kW Transducer 8pin

010-11869-20
$818.95
SS164 0 deg tilt 1kW Transduce

GARMIN SS164 12 deg tilt 1kW Transducer 8 pin

010-11869-21
$818.95
SS164 12 deg tilt 1kW Transduc

GARMIN SS164 20 deg tilt 1kW Transducer 8 pin

010-11869-22
$818.95
SS164 20 deg tilt 1kW Transduc

Airmar For Garmin SS260 HD DT Cone 19/6 1kW 200/50KHz Steel 8pin Transducer

SS260-8G
$1,028.95
For Garmin SS260 HD DT Cone 19

GARMIN SS270W-8G 1kW 200/50kHz,Cone 25, Thru-Hull,8pin Transducer

010-11140-20
$1,530.95
SS270W-8G 1kW 200/50kHz,Cone 2

GARMIN SS60 0 deg tilt 50/200 kHz Transducer

010-11868-20
$355.95
SS60 0 deg tilt 50/200 kHz Tra

GARMIN SS60 12 deg tilt 50/200 kHz Transducer

010-11868-21
$355.95
SS60 12 deg tilt 50/200 kHz Tr

GARMIN SS60 20 deg tilt 50/200 kHz Transducer

010-11868-22
$355.95
SS60 20 deg tilt 50/200 kHz Tr

Transducers Garmin 8-pin/bare wires Transom (Transducer Guide)

GARMIN P66 Transom 200/50kHz plastic Standard Differential Transducer 8-pin

010-10272-10
$74.95
P66 Transom 200/50kHz plastic

GARMIN P32-8G DST 77/200 Khz 45/15 beam Transom Mount 8pin Triducer

010-10106-20
$142.95
P32-8G DST 77/200 Khz 45/15 be

GARMIN P66 500W 77/200 kHz Transducer, 8-pin

010-10249-40
$72.95
P66 500W 77/200 kHz Transducer

Airmar For Garmin Cone 19/6 1kW 50/200KHz 8pin Tank-Mount Transducer

CM260-8G
$830.95
For Garmin Cone 19/6 1kW 50/20

Airmar For Garmin Beam 25 1kW 50/200KHz 8pin Tank-Mount Wide-Beam Transducer

CM270W-8G
$995.95
For Garmin Beam 25 1kW 50/200K

010-10192-21
$134.95
P66 200/50kHz plastic Transduc

GARMIN TM260 1kW DT 200/50kHz plastic Transom Mount 8pinTransducer

010-11395-20
$882.95
TM260 1kW DT 200/50kHz plastic

Airmar For Garmin TM260 1kW DT 200/50kHz plastic Transom Mount 6pinTransducer

010-11395-00
$789.95
For Garmin TM260 1kW DT 200/50

Airmar For Garmin TM258-8G DT Cone 3-21 1kW 200/50kHz Transom 8pin Transducer

TM258-8G
$560.95
For Garmin TM258-8G DT Cone 3-

List of Compatible Units:

	GARMIN GPSMAP 1022
	GARMIN GPSMAP 1022xsv
	GARMIN GPSMAP 1042xsv
	GARMIN GPSMAP 1042xsv with Transducer
	GARMIN GPSMAP 1222
	GARMIN GPSMAP 1222xsv
	GARMIN GPSMAP 1242xsv
	GARMIN GPSMAP 1242xsv with Transducer
	GARMIN GPSMAP 2206
	GARMIN GPSMAP 276C
	GARMIN GPSMAP 276C Plus NOH
	GARMIN GPSMAP 278
	GARMIN GPSMAP 296
	GARMIN GPSMAP 3005C NOH
	GARMIN GPSMAP 3005C
	GARMIN GPSMAP 3006C
	GARMIN GPSMAP 3006C NOH
	GARMIN GPSMAP 3010C
	GARMIN GPSMAP 3205
	GARMIN GPSMAP 3205 NOH
	GARMIN GPSMAP 378 NOH
	GARMIN GPSMAP 378
	GARMIN GPSMAP 396
	GARMIN GPSMAP 420 NOH
	GARMIN GPSMAP 420
	GARMIN GPSMAP 420s no transducer
	GARMIN GPSMAP 420s with transducer
	GARMIN GPSMAP 420s with transducer NOH
	GARMIN GPSMAP 421
	GARMIN GPSMAP 421 NOH
	GARMIN GPSMAP 430
	GARMIN GPSMAP 430 NOH
	GARMIN GPSMAP 430s with transducer
	GARMIN GPSMAP 430s with transducer NOH
	GARMIN GPSMAP 431
	GARMIN GPSMAP 431 NOH
	GARMIN GPSMAP 440
	GARMIN GPSMAP 440 NOH
	GARMIN GPSMAP 440s no transducer
	GARMIN GPSMAP 440s with transducer
	GARMIN GPSMAP 440s with transducer NOH
	GARMIN GPSMAP 441
	GARMIN GPSMAP 478 NOH
	GARMIN GPSMAP 478
	GARMIN GPSMAP 495
	GARMIN GPSMAP 496
	GARMIN GPSMAP 520 NOH
	GARMIN GPSMAP 520
	GARMIN GPSMAP 520s no transducer
	GARMIN GPSMAP 520s no transducer NOH
	GARMIN GPSMAP 520s with transducer
	GARMIN GPSMAP 520s with transducer NOH
	GARMIN GPSMAP 521
	GARMIN GPSMAP 521 NOH
	GARMIN GPSMAP 525 NOH
	GARMIN GPSMAP 525
	GARMIN GPSMAP 525s no transducer NOH
	GARMIN GPSMAP 525s no transducer
	GARMIN GPSMAP 525s with transducer NOH
	GARMIN GPSMAP 525s with transducer
	GARMIN GPSMAP 530
	GARMIN GPSMAP 530 NOH
	GARMIN GPSMAP 530s with transducer
	GARMIN GPSMAP 531
	GARMIN GPSMAP 531 NOH
	GARMIN GPSMAP 535 NOH
	GARMIN GPSMAP 535
	GARMIN GPSMAP 535s with transducer
	GARMIN GPSMAP 535s with transducer NOH
	GARMIN GPSMAP 535s without transducer NOH
	GARMIN GPSMAP 536
	GARMIN GPSMAP 540
	GARMIN GPSMAP 540s no transducer
	GARMIN GPSMAP 540s with transducer
	GARMIN GPSMAP 541
	GARMIN GPSMAP 545 NOH
	GARMIN GPSMAP 545
	GARMIN GPSMAP 545s no transducer
	GARMIN GPSMAP 545s with transducer NOH
	GARMIN GPSMAP 545s with transducer
	GARMIN GPSMAP 545s without transducer NOH
	GARMIN GPSMAP 722
	GARMIN GPSMAP 722xs
	GARMIN GPSMAP 7407
	GARMIN GPSMAP 7407 J1939
	GARMIN GPSMAP 7407xsv
	GARMIN GPSMAP 7407xsv J1939
	GARMIN GPSMAP 7408
	GARMIN GPSMAP 7408 J1939
	GARMIN GPSMAP 7408xsv
	GARMIN GPSMAP 7408xsv J1939
	GARMIN GPSMAP 7410
	GARMIN GPSMAP 7410 J1939
	GARMIN GPSMAP 7410xsv
	GARMIN GPSMAP 7410xsv J1939
	GARMIN GPSMAP 7412
	GARMIN GPSMAP 7412 J1939
	GARMIN GPSMAP 7412xsv
	GARMIN GPSMAP 7412xsv J1939
	GARMIN GPSMAP 7416
	GARMIN GPSMAP 7416 J1939
	GARMIN GPSMAP 7416xsv
	GARMIN GPSMAP 7416xsv J1939
	GARMIN GPSMAP 742
	GARMIN GPSMAP 742xs
	GARMIN GPSMAP 7607
	GARMIN GPSMAP 7607 J1939
	GARMIN GPSMAP 7607xsv
	GARMIN GPSMAP 7607xsv J1939
	GARMIN GPSMAP 7608
	GARMIN GPSMAP 7608 J1939
	GARMIN GPSMAP 7608xsv
	GARMIN GPSMAP 7608xsv J1939
	GARMIN GPSMAP 7610
	GARMIN GPSMAP 7610 J1939
	GARMIN GPSMAP 7610xsv
	GARMIN GPSMAP 7610xsv J1939
	GARMIN GPSMAP 7612
	GARMIN GPSMAP 7612 J1939
	GARMIN GPSMAP 7612xsv
	GARMIN GPSMAP 7612xsv J1939
	GARMIN GPSMAP 7616
	GARMIN GPSMAP 7616 J1939
	GARMIN GPSMAP 7616xsv
	GARMIN GPSMAP 7616xsv J1939
	GARMIN GPSMAP 922
	GARMIN GPSMAP 922xs
	GARMIN GPSMAP 942
	GARMIN GPSMAP 942xs

Note: Displayed are products sold in gps4us store.
There might be more GPS units compatible with chosen accessory.

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