LS-3 Series compact, plastic liquid level switches from Gems Sensors & Controls Inc., Plainville, CT, sense level in shallow tanks, restricted spaces, or other low-cost high-volume uses. The switch uses a magnet-equipped float to actuate a hermetically sealed reed switch within the unit's stem. Models are available for temperatures from –40°C to 121°C, pressures to 150 psi, and in a variety of engineering plastics, including polysulfone, polypropylene, and FDA-approved PVDF.