B258 Depth/Temperature Transducer

Part # 179-0401-017.

The B258 is a bronze, thru-hull Broadband transducer, ideal for smaller sportfishing and commercial vessels up to 8 m (25 ft) in length, fishing in depths of less than 900m (3000 ft).

Key Features

  • 50 kHz with 15° port/starboard beam width (21° fore/aft)
  • 200 kHz with 3° port/starboard beam width (5° fore/aft)
  • Up to 900 m (3000 ft) range at 50 kHz
  • 4 internal broadband ceramics
  • Thru-Hull with bronze housing and high-performance fairing
  • Suitable for fiberglass and wood hulls
  • Ideal for sportfishing and commercial vessels up to 8 m (25 ft) in length
  • Recommended for use with the SonarHub sounder module, Simrad NSS evo2 & NSS sport multifunction displays
Where To Buy

    Dual Frequency

    The dual-frequency B258 includes an array of four ceramic elements delivering both 50 kHz with a 15° port/starboard beam width (21° fore/aft), and 200 kHz with a 3° port/starboard beam width (5° fore/aft). 50 kHz low-frequency operation offers a maximum operational depth of 900 m (3000 ft), while 200 kHz high-frequency provides higher-resolution fish arches and bottom detail in shallower water.


    One sensor does it all. Able to measure both depth and temperature in a single package, the B258 simplifies installation and requires just one connection to your echosounder module or multifunction display.


    With bronze housing, the B258 is suitable for thru-hull mounting in fiberglass and wood hulls. Thru-hull mounting places the transducer in the water on the outside of your boat’s hull; a hole must be drilled for installation, and a fairing block is required to ensure proper alignment. This typically offers the best depth measurement and fishfinding performance.

    Calculate the beamwidth for this transducer

    B258FrequencyCone AngleBeamwidth
    200 kHz  
    50 kHz 21°  
    Depth: Update
    NB: depending on the strength of your transducer pulse