Service Intended Suitable for media such as air, water, oil & gases that do not attack copper alloy or stainless steel parts or will obstruct the pressure system. Typical applications will be for the control and regulation of industrial processes where switching of electrical circuits are required. Externally adjustable, single or double contacts, can be fitted to a SA Gauge pressure gauge to make the gauge suitable to activate or deactivate electrical devices. Contact can make or break in an upward or downward pressure cycle.