Clark-Reliance Corporation is a privately held family business that has positioned itself as the largest level indicator supplier in the world. The Jerguson Gage & Valve Division invented the magnetic level gage and offers the world's largest selection of armored and tubular gage glasses, magnetic gages and accessories such as valves, scales, switches, transmitters and illuminators. Jerguson also manufactures high quality eductors, also known as jet pumps, to full ANSI specifications with unique captured o-ring seals and bar stock nozzles.

The Magne-Sonics Division offers a complete line of bouyancy, capacitance, ultra-sonic and tuning fork level switches and transmitters.