Mid-Pressure Switches. Medium pressure switches: 25 psi to 500 psi, factory set or field adjustable, gold contacts, 4000/6000 proof, easily configurable, many ports & terms. Low-Pressure Switches. Low pressure switches: 3.5 psi to 150 psi, factory set & field adj., gold contacts, hysteresis & smart diagnostic tech. options, many ports and terms.