The ST864 is a rugged, sealed sensor designed for the SA864 high pressure ball valve insertion / retraction assembly. The patented solid state reference cell features the unique IonTrap™ design for extended service life in the most severe applications. The body, with an integral bulb guard, is moulded from chemically resistant Kynar and the reference junction is porous Teflon. Built-in temperature compensators are available. Sensor also available in ORP (Redox) version.