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Sonde FD-20 (20ft depth.0.75"W)

Sonde FD-20 (20ft depth.0.75"W)


Standard Sonde for locating out empty duct
Measures: 0.75" x 4"
Frequency: 512kHz
Depth Range: 14 feet in cast iron | 23 feet in nonmetallic
Battery type: 1 x AAA alkaline battery
Connect to a Flexrod using a Spring Carrier

This is a self-contained, battery-operated sonde. It can be connected to a Flexrod for locating pipes and ducting using a Spring Carrier. It transmits on 512Hz.  It can be normally located to a maximum depth of 23 feet.

The FD-20 is the most popular transmitter in our 512 Hz line for locating in cast iron and nonmetallic lines. And now with its new more durable design the FD-20 is ready to transmit even in the toughest terrain.

  • Steel head for durability
  • Encased in a strong polycarbonate tube.
  • Watertight
  • Brass battery cap and 1 AAA alkaline battery included
  • Will work with any receiver that uses the 512 Hz frequency. For best results use one of our LineFinders
  • Our Spring Carriers are recommended to help protect your transmitter
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