Service Tracer Application Signal Transmitter and Locator to Trace Non-Conductive Ducts or Pipes up to 4 in Diameter Cable Length 263 ft Color Yellow Features Can be Used in Line or Sonde Mode to Trace the Route of the Duct or a Blockage For Use With Signal Transmitters Operating Frequency Not Applicable Outside Diameter 0.2 in Product Type Trace Rod For Modes Line Sonde For Use On Non-Conductive Ducts or Pipes Material Fiberglass Rod over Copper Wire Overall Depth 17.3 in