www.thedriller.com/articles/84694-general-purpose-submersible-level-transmitter
General-purpose Submersible Level Transmitter
February 1, 2006

The Levelgage by Keller America Inc. is designed for indefinite submersion in a wide variety of liquid media. It provides temperature-compensated analog output proportional to the height of the liquid column above the transmitter. This submersible level transmitter is intended for general-purpose monitoring and control applications, including ground water, potable water, wet wells, monitoring wells, tanks, reservoirs and more.
Keller America Inc., Card No. 224