Garmin Transom Trolling Transducer for echo Series Fishfinders 4-Pin
Garmin Transom Trolling Transducer for echo Series Fishfinders 4-Pin — Product description
The Garmin Transom/Trolling Motor Transducer for echo Series Fishfinders (MPN 010-10249-20, UPC 753759974183) is a dual-beam 77/200 kHz, 500-watt, 4-pin replacement or spare transducer for the Garmin echo series of CHIRP-era fishfinders (echo 100, 150, 200, 300c, 500c, 550c) and STRIKER series fishfinders that use the same 4-pin connector. The kit includes mounting hardware for transom mount installation (0-70 degree transom angle range) OR clamp-on trolling motor shaft mounting - one transducer, two mounting options, depending on which install path makes sense for your boat. Dual-beam frequency operation gives you two views: the 77 kHz wide beam (45-degree cone) covers a broad swath of water for searching - good for finding suspended baitfish, school structure, or unknown bottom drop-offs. The 200 kHz narrow beam (15-degree cone) delivers detailed individual-target separation - good for identifying single fish on a brush pile or distinguishing hardpan from mud bottom. The 500W power rating is sufficient for the 1900 ft max depth claim in ideal conditions (clear water, calm surface, hard bottom) and realistic 200-400 ft useful depth in typical freshwater fishing scenarios. 30 ft cable length covers most installs from transom to typical helm-mounted echo display location without splicing. Built-in temperature sensor reads water surface temperature - shows on the echo display alongside depth, useful for finding the thermocline where summer bass and walleye stack up. This is the same transducer that originally shipped with new echo-series units - sold as a spare for second boats, replacement for damaged or lost units, or as the part you need when re-installing an echo unit on a different boat without the original transducer. NOTE: On echo 100 (single-beam unit), this transducer operates at 200 kHz only - the echo 100 doesn't support the 77 kHz mode regardless of transducer capability. 1-year limited Garmin warranty.
The Garmin Transom/Trolling Motor Transducer for echo Series (010-10249-20) is the factory dual-beam transducer for Garmin's echo and STRIKER 4-pin fishfinders. This is the exact transducer that originally shipped with new echo-series units, sold separately as a replacement when the original is damaged, lost, or stays with another boat, or as a spare for a second boat setup where you swap one display between two boats.
Compatibility - the exact list. The 010-10249-20 is the 4-pin transducer for: Garmin echo 100, echo 150, echo 200, echo 300c, echo 500c, echo 550c. It also works with the STRIKER 4 / 5 / 7 / 9 series fishfinders that share the same 4-pin connector. It does NOT work with: STRIKER Plus and STRIKER Vivid series (those use a different connector and CHIRP transducer), GT-series CHIRP transducers (different connector), older Garmin Fishfinder 80/90/100/140/160/240/250/300 (different connector), or any other-brand fishfinder. Verify your fishfinder model and transducer connector pin count before ordering - the 4-pin connector is the key identifier.
The dual-beam frequency feature. The 010-10249-20 is a dual-beam transducer running 77 kHz and 200 kHz simultaneously (with the echo display electronically switching between them or showing both on a split screen). What each frequency does: The 77 kHz wide-cone beam (45-degree cone width) covers a large area of water at any given depth - at 100 ft depth, the 77 kHz cone covers about an 80 ft diameter circle on the bottom. Useful for searching: finding suspended fish schools, identifying broad bottom contour changes, locating bait clouds. The 200 kHz narrow-cone beam (15-degree cone width) covers a much smaller area but with higher detail - at 100 ft depth, about a 25 ft diameter circle. Useful for targeting: counting individual fish on structure, separating fish from bottom, distinguishing hard bottom from soft. Anglers typically run both frequencies in a split-screen view - search with the wide beam, target with the narrow beam.
Echo 100 exception. The echo 100 is the entry-tier single-beam unit in the echo lineup - it only processes one frequency at a time and Garmin spec'd it for 200 kHz only. If you mount the 010-10249-20 dual-beam transducer on an echo 100, the unit will only use the 200 kHz beam (no 77 kHz wide-beam capability). This is a unit limitation, not a transducer limitation - the transducer still produces both frequencies, but the echo 100 hardware can only listen to one. Buyers with echo 100 units: this transducer still works, you just don't get dual-beam operation. The narrow 200 kHz beam is fine for most freshwater fishing applications anyway, just keep your expectations matched to the hardware capability.
500 watts and 1900 ft depth - the realistic version. Garmin's spec sheet calls out 500 watts power and 1900 ft maximum depth capability. The 1900 ft depth claim is the theoretical maximum under absolute ideal conditions (zero noise, hard rocky bottom, perfectly calm surface, fresh water, slow boat speed). Realistic depth performance in actual fishing scenarios: 300-600 ft on typical freshwater lakes with soft to medium bottom, 200-400 ft when running at 25+ mph, 400-800 ft over hard rocky bottom in clear deep lakes. For typical bass/crappie/walleye/perch freshwater fishing in the 5-150 ft range, the transducer delivers reliable performance with margin to spare. The 500W rating is also a reasonable match for the echo display electronics - higher-wattage CHIRP transducers wouldn't deliver more useful performance because the echo unit's sonar processing is the limiting factor.
Mounting options - transom or trolling motor. The kit includes hardware for both common mounting configurations. Transom mount installation: bracket bolts to the transom with the transducer face hanging below the bottom of the hull, angled so the bottom face runs parallel to the waterline at planing speed. Recommended location: 1/3 of the way from boat centerline toward starboard, away from prop wash. Trolling motor mount: clamp adapter (included) attaches the transducer to the lower shaft of a bow-mount trolling motor just above the prop. Trolling motor mount is the preferred option for serious electronics fishing - the transducer always stays submerged, never breaks the surface during turns, and gets the sonar reading from the bow rather than the stern (useful when targeting structure ahead of the boat). For most owners who want a quick transom mount install: 30-60 minute job with a drill, level, and basic hand tools.
30 ft cable length. The cable runs 30 feet from the transducer to the 4-pin connector that plugs into the echo display. For most installations - transducer on the transom or trolling motor, display at the helm console - 30 ft is sufficient with cable to spare. The excess cable should be coiled neatly and secured (don't cut it off, you may need the length later if you move the display). For installations where the cable run exceeds 30 ft (large boats, displays mounted far from the transducer), Garmin sells extension cables - the connection is at the transducer end and you can extend the cable run with the proper extension. Don't cut and splice the cable yourself - the 4-pin connector and shielding are specifically engineered for the sonar signal integrity and field-splices typically degrade performance.
Temperature sensor. Built into the transducer body is a temperature sensor that reads water temperature at the transducer face. The echo display shows this temperature in the data bar alongside depth and other readings. Useful for finding the thermocline where summer fish stack up at the temperature transition, identifying water masses (warmer cove water vs cooler open lake water), and tracking seasonal patterns. The temperature reading is accurate to about +/- 1 degree F under normal operating conditions.
0 to 70 degree transom angle range. The transom mount bracket adjusts to fit transoms angled from 0 degrees (vertical, like an inboard cruiser) to 70 degrees (extreme angled, like some flat-bottom jon boats). Most outboard-powered boats have 10-15 degree transom angles - well within the bracket's range. If your transom is angled steeper than 70 degrees (rare), you'll need a special wedge shim or a different transducer mount strategy. Confirm transom angle by measuring with a level if you're unsure before ordering.
What's included. The transducer with attached 30 ft cable and 4-pin connector, transom mount bracket and stainless hardware, trolling motor clamp adapter, installation instructions. No echo unit included - this is the transducer only, sold separately.
1-year limited Garmin warranty. Standard Garmin marine product warranty. Register the product on Garmin's website for warranty activation. Warranty covers manufacturing defects in materials and workmanship, does not cover damage from impact (hitting underwater obstacles at speed), cable damage from improper routing, or lightning damage.
Key Features
- Factory dual-beam 4-pin transducer for Garmin echo series fishfinders (echo 100, 150, 200, 300c, 500c, 550c) and STRIKER 4/5/7/9 series
- Dual frequency operation: 77 kHz wide beam (45-degree cone) for searching + 200 kHz narrow beam (15-degree cone) for targeting individual fish and structure detail
- 500 watts of sonar power with 1900 ft maximum depth capability in ideal conditions (realistic 200-600 ft in typical freshwater fishing)
- Mounting hardware included for BOTH transom mount (0-70 degree transom angle) AND trolling motor shaft mount - one transducer, two install options
- 30 ft cable length sufficient for most transom-to-helm or trolling-motor-to-helm cable runs without splicing
- Built-in water temperature sensor reads surface temperature - shows on echo display for thermocline and water-mass identification
- Plastic transducer body with corrosion-resistant fasteners - freshwater rated, handles light saltwater service with fresh-water rinse routine
- Same factory transducer that originally shipped with new echo-series units - exact OEM replacement or spare
- NOTE: On echo 100 (single-beam unit), this transducer operates at 200 kHz only due to echo 100 hardware limitation - dual-beam is unit-dependent
- Compatible with most STRIKER series fishfinders that use the 4-pin connector (NOT STRIKER Plus or STRIKER Vivid - those use a different connector)
- Mounts on transom 1/3 distance from boat centerline toward starboard for best performance away from prop wash
- 1-year limited Garmin warranty
Why Buy from NVN Marine
- Authorized Garmin reseller, full manufacturer warranty
- NMEA member and ABYC certified, advice from real boat techs
- Same-day shipping before 3 PM ET on in-stock items
- NY headquarters and Fort Lauderdale flagship retail store
Genuine Garmin 010-10249-20 transducer - the factory part for echo and 4-pin STRIKER fishfinders. Ships from NVN Marine with order-by-3-PM same-day shipping. Backed by Garmin's 1-year limited warranty.
Technical specifications
| Title | Garmin Transom/Trolling Motor Transducer for echo Series Fishfinders (4 Pin) |
|---|---|
| Brand | Garmin |
| Manufacturer Part Number | 010-10249-20 |
| UPC | 753759974183 |
| Connector | 4-pin (Garmin echo series and original STRIKER series) |
| Compatible Units | Garmin echo 100, 150, 200, 300c, 500c, 550c. STRIKER 4, 5, 7, 9 (NOT STRIKER Plus or Vivid) |
| Beam Type | Dual beam (77 kHz wide + 200 kHz narrow, runs simultaneously) |
| Frequency | 77 kHz / 200 kHz |
| Beam Width | 45 degrees (77 kHz) / 15 degrees (200 kHz) |
| Power Rating | 500 watts |
| Maximum Depth | 1900 ft (ideal conditions). realistic 200-600 ft in typical fishing |
| Cable Length | 30 feet |
| Mount Type | Transom (0-70 degree angle range) OR trolling motor shaft clamp (both hardware kits included) |
| Temperature Sensor | Built-in (reads water surface temperature, +/- 1 degree F accuracy) |
| Speed Sensor | Not included |
| CHIRP Capable | No (standard fixed-frequency dual-beam) |
| Body Material | Plastic with stainless mounting hardware |
| Water Rating | Freshwater and saltwater rated |
| Special Note | On echo 100, operates at 200 kHz single-beam only (unit limitation, not transducer) |
| What's Included | Transducer with 30 ft cable, transom mount bracket and hardware, trolling motor clamp adapter, install guide |
| Warranty | 1-year limited (Garmin standard) |
Frequently asked questions
Which Garmin fishfinders does this transducer work with?
The 010-10249-20 is the 4-pin transducer for: Garmin echo 100, echo 150, echo 200, echo 300c, echo 500c, echo 550c, plus STRIKER 4, STRIKER 5, STRIKER 7, STRIKER 9 (the original STRIKER series that use the 4-pin connector). It does NOT work with: STRIKER Plus, STRIKER Vivid, ECHOMAP series, GPSMAP series, or any unit that uses the newer GT-series CHIRP transducer connector. Check your fishfinder's transducer port pin count - 4 pins means this transducer fits, other pin counts mean you need a different transducer.
Will it work on the STRIKER Plus 4/5/7/9?
No. The STRIKER Plus uses a different transducer connector (the GT20-TM CHIRP transducer with a different pin pattern). The 4-pin 010-10249-20 transducer is only for the original STRIKER series (without 'Plus' in the name). Verify your model name carefully - the Plus and non-Plus look similar from the front but use different transducers.
What's the difference between transom mount and trolling motor mount?
Transom mount installs on the back of the boat below the waterline - bracket bolts to the transom, transducer hangs below the hull, sonar reading comes from the stern. Trolling motor mount clamps the transducer to the lower shaft of a bow-mount trolling motor just above the prop - sonar reading comes from the bow. Most owners with bow-mount trolling motors prefer the trolling motor mount because (1) the transducer always stays submerged regardless of speed/turns, (2) you read the bottom in front of the boat rather than behind, useful for structure fishing, and (3) no permanent holes drilled in the transom. The kit includes hardware for both mounting options - choose at install time.
How do I install the transom mount?
1) Choose a location on the transom 1/3 of the way from centerline toward starboard, below the waterline, away from prop wash. 2) Mark and drill pilot holes for the bracket bolts. 3) Apply marine sealant to the screw holes. 4) Bolt the bracket securely with stainless hardware (included). 5) Slide the transducer into the bracket and adjust the angle so the bottom face runs parallel to the waterline at planing speed (typically the bracket bottom is slightly toward the bow at rest). 6) Tighten the angle-adjustment bolts. 7) Route the cable through the transom (drill and seal a small hole) to the display. Test at idle and planing speeds, fine-tune the angle for bottom lock at speed. Total time: 30-60 minutes.
How do I install on a trolling motor?
Use the included clamp adapter to attach the transducer to the lower shaft of your trolling motor, positioned just above the prop with the transducer face pointing straight down. Don't position it so close that the prop wash directly hits the face (causes turbulence and noise) or so high that it breaks the water surface during sharp turns. The clamp tightens with included hardware. Route the cable up the motor shaft secured with cable ties (don't tighten so hard the cable abrades against the shaft). The trolling motor install takes about 15-20 minutes and requires no transom drilling.
What's the realistic depth performance?
In typical freshwater fishing conditions: 200-400 ft when running at 25+ mph (cavitation reduces effective depth at speed), 300-600 ft at trolling speed over typical soft-to-medium freshwater bottoms, 400-800 ft over hard rocky bottoms in clear deep lakes (Lake Superior, Tahoe, etc). The 1900 ft theoretical maximum is achievable only in absolute ideal conditions and not realistic for normal fishing scenarios. For 95% of freshwater fishing situations (5-150 ft range), the transducer delivers reliable performance with significant margin.
Does it work in saltwater?
Yes, but with caveats. The transducer is rated for both freshwater and saltwater service, but the echo series fishfinders themselves are entry-tier units oriented toward freshwater fishing - they lack the saltwater-specific features (water temperature compensation, salt-water chart overlays, etc.) of higher-end Garmin marine units. For occasional saltwater bay fishing, the combination works. For serious offshore saltwater use, you'd want to step up to an ECHOMAP or GPSMAP unit with the matching saltwater-rated CHIRP transducer. Always rinse the transducer with fresh water after saltwater exposure.
What does the temperature sensor do?
Reads water temperature at the transducer face and displays the reading on the echo unit's screen alongside depth. Useful for identifying the thermocline where summer fish stack up (sharp temperature transition typically at 15-30 ft depth in summer), tracking water masses (cooler vs warmer cove water), and seasonal pattern fishing where temperature is a primary catch variable. Accuracy is +/- 1 degree F under typical conditions. No additional setup required - the echo unit auto-detects the temperature reading from the transducer.
Can I cut the cable shorter or splice in an extension?
Don't cut the cable - if you have excess length, coil and secure it neatly. The cable connector and shielding are engineered for sonar signal integrity and field-splices typically degrade performance with mysterious noise issues that are hard to diagnose later. If you need MORE cable than the 30 ft included, Garmin sells extension cables that connect at the transducer end - use those rather than splicing. The connector is keyed so it can only attach one way.
What if my transom angle is steeper than 70 degrees?
The transom mount bracket fits 0-70 degree transom angles. For steeper angles (very rare, mostly flat-bottom jon boats with extreme rake), you'll need either a wedge shim under the bracket to compensate, or switch to the trolling motor mount option (which works regardless of transom angle), or use a thru-hull transducer install (different product, requires hull drilling). Measure your transom angle with a level if you're unsure - most outboard-powered boats are well within the 70-degree limit.
Will I see fish arches with this transducer?
Yes - the dual-beam transducer paired with an echo or STRIKER unit shows the classic fish arch pattern when fish pass through the sonar cone. Arch size and clarity depend on fish size, depth, boat speed, and how the fish crosses the beam. The 200 kHz narrow beam typically delivers sharper arches because the fish stays in the beam longer. The 77 kHz wide beam shows more fish overall but with less individual definition. Practice reading the sonar in known-good water (a lake where you know there are fish at a specific depth) to calibrate your eye for what fish vs structure vs noise looks like.
What's the warranty?
1-year limited Garmin warranty covering manufacturing defects in materials and workmanship. Register the product on Garmin's website for warranty activation. Warranty doesn't cover impact damage (hitting underwater obstacles at speed kills transducers regularly), cable damage from improper routing, lightning damage, or normal wear. Failures within the warranty period are typically handled by exchange through Garmin authorized service.
