In a typical cable or pipe survey the Spar is mounted vertically on a survey pole directly below the GNSS receiver. The surveyor monitors the display continuously, using the on-screen indicators to maintain casual contact with the utility center line. Measurements may be collected automatically at fixed intervals or with single-shot measurements at selected locations. The pole may be equipped with a survey wheel for convenience. When the measurement range of the Spar needs to be extended, either because the utility is buried deeper than the 10 ft. (3 m) range of a single spar or because access to the centerline is restricted or difficult, two Spar 300 PPS units may be mounted together on a cart or a vehicle. The separation of the Spars determines how much the range is extended, for example, a 6 ft. (2 m) separation yields about 40 ft. (12 m) range.