WL500 Well Level Sounder sets a new precision standard for well water level measurement.  The Water Level Sounder meets or exceeds federal specification US GGG-T-106E (USA) or EEC CLASS II (Europe) for a guaranteed accuracy of 0.008%.  The Water Level Sounder uses a full depth-rated stainless steel and teflon probe that is 5/8-inch (16 mm) in diameter.  The water level sounder's sensor electronics are encapsulated in water and dust proof housing.  The flat spring steel core ensures that the level sounder will hang perfectly straight in large and small diameter wells.  This provides unparalleled accuracy when compared to the flat white tapes, where kinks in the tape introduce slight errors, in addition to the displacement of water changing the static level.

The water level sounder uses a shrouded probe with a unique design to prevent bridging.  Bridging is often encountered during pump tests with similar water level sounders.  All WL500 Well Level Sounders carry a sensitivity adjustment for different water qualities.  This sensitivity control prevents false readings in high conductivity water and is ideal for pump and draw down tests.  When the water level sounder's probe assembly makes contact with the surface of the water, a bright LED glows and a beeper sounds on the reel.

The well level sounder consists of a strong NTS-certified polyethylene jacketed measuring tape that will accurately read to 0.01 foot or 1 mm.  The tape reels are built of resistant polycarbonate (or, for units with over 400 ft cable, of lighter aluminum).

The depth sounder is battery operated, thus there is no danger of shock from an outside power supply.  Two conductors make a separate ground connection unnecessary, so the instrument will function equally well in uncased test holes or in uncased wells in rock.  Water entering the well from casing leaks or perforations about the water level will not affect the depth gauge's measurements.