The SL172 will tell you

The Signet Marine SL172 is a sailboat depth sounder which features advanced algorithms that automatically compensate for boundary thermal layers, multiple echos, listing, hull turbulence and varying bottom conditions. Advanced microprocessor logic, along with time-proven transducer design provide sensitivity to bottom contour variations as small as one-tenth of a foot under normal operating conditions.

The SL172 Depth Sounder consists of two major components: The instrument display, which contains the electronics, alarm, and Liquid Crystal Display (LCD), and the depth transducer. The transducer is available in flush, mushroom, extractable, or brass configurations.

For greater peace-of-mind, the SL172 was designed with a forward-trending alarm. This alarm sounds up to twenty seconds before you reach a preset alarm depth by calculating a trend in decreasing depth readings. The Signet Marine SL172 Depth sounder offers affordability and security in one convenient package.

Each unit is vigorously tested and must pass extensive quality control standards before it is shipped. All units come with a two-year warranty.

Instrument Dimensions

Main Features
Large, High-Contrast LCD
Forward-Trending Alarm
3 - 200 Foot Range
200 kHz Transducer w/ 18° beam
Adjustable Keel Offset
Red Night Lighting
Complete with Sensor and Hardware

Mounting Options
Sensor: Flush, Mushroom, Extractable or Bronze
Indicator: Bulkhead or Panel Mounting


Power Requirements
Instrument: 12 VDC
Lighting: 12 VDC
Power: 250 mA


The Signet Marine SL172 depth sounder combines low power drain with precise accuracy and high reliability. A perfect match for the SL267A.
speed sensor
paddlewheel flush thru hull and plug

What's in the box?
The complete system includes:

  • SL172 Depth sounder
  • Your choice of depth transducer
  • Instruction Manual and Mounting Hardware

SL172 with Flush Transducer: (M17200-10)  $485
SL172 with Mushroom Transducer: (M17200)  $485
SL172 with Extractable Transducer: (M17200-30)  $485
SL172 Instrument Only: (M17240) $419

Note: All transducers are manufactured with 35 feet of cable (non-extendable).


Mushroom Transducer

flush transducer