A switch design that combines gold crossbar contacts with an all-in-one-welded contact terminal construction that delivers reliability and extended life in harsh low-pressure environments. The MAM005 line of ultra-low pressure, vacuum, and differential switches can be ordered preconfigured for immediate shipment, as a standard product tailored to user needs, or custom-designed for special applications. The switches come configured with different port orientations to fit mounting requirements and come in nine different diaphragm materials. The devices can be selected to assure chemical compatibility with most mediums and reliable operation at temperature extremes.