A unique patented Magnetic Linkage in the S-D™ Liquid Level Switch isolates the electrical compartment, containing one or two switches, from controlled product. This reduces maintenance and improves sensitivity. The sealed switch compartment and sealed leads yield highly reliable operation. A variety of switch types, options, mounting choices and thumbwheel adjustable ranges is available to fit your specific application. The S-D™ is very sensitive and economical. The force required to depress the diaphragm and trip the switch(es) is in inches water column. See "Complete Model Chart" on for details. The simple design has been proven rugged and reliable providing long life in the most severe applications.