TM258 1kW Transom Mount Transducer w/Humminbird 9 Plug – 7-Pin
The re-designed TM258 sports a new look and better high-speed performance. The industry’s first, 1kW, transom-mount transducer has an updated, rugged, mounting bracket. The sleek design makes the TM258 easier to install. And its streamlined shape will give you improved high-speed performance up to 30 knots (35 MPH).
The TM258 will make 600W sounders respond like a more-powerful model. Get 16-times the sensitivity compared with a standard transom-mounted transducer. The TM258 packs four, 50 kHz/200 kHz elements to focus narrow beams at both frequencies, so you’ll see crisp targets and clear bottom definition.
Features:
- Depth & fast-response water-temperature sensor
- Elliptical beam covers larger bottom area
- Fits existing TM256 and TM258 models
- Bracket kick-up assembly locks in the “up” position and will not damage the transom
- Accommodates transom angles between 3° and 21°
- Urethane transducer housing
- Boat Size: Up to 12M (40′)
Specifications:
- Weight: 3.6kg (7.9lb)
- Hull Deadrise: Up to 25°
- Acoustic Window: Urethane
This product may not be returned to the original point of purchase.Please contact the manufacturer directly with any issues or concerns.
Specifications:
- Temperature: Yes
- Mounting Style: Transom
- Pins: 7
Quick Guide (pdf)
Owner’s Manual (pdf)
Brochure (pdf)

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