The Edwards range of passive ion gauges both Bayard-Alpert and Extractor Ion gauge heads which together can measure from atmosphere down to 10-12 mbar. These are used in conjunction with a Passive gauge controller (PGC) to display pressure and offer an intuitive interface for the user alongside the ability to control remotely. Edwards will offer 2 controller variants; the PGC201 which covers the Pressure range of 10-9 to 1000 mbar, in conjunction with Pirani and Penning gauges, and the PGC202 which covers the wider range of and 10-12 to 1000 mbar when used with a Pirani and Ion gauge.