A² Probe

A²™ Probe

100% solid zirconia oxygen sensor

All the best features you’ve come to expect from the AccuCarb® and AtmoProbe™ are now combined into one new product series, the A²™. This solid zirconia electrolyte probe is the result of extensive research and developmental testing, and with its many patented innovations, the A² represents a major breakthrough in probe design.

The design of the A²™ has been field-proven for the past 40 years to provide the most robust and reliable atmosphere measurement solution available. In “side-by-side” trials in carburizing atmosphere applications, the A²™ has repeatedly shown to provide the most accurate measurement of true carbon potential over an extended period of time without any “process factor” adjustments necessary.

Available in a selection of sizes and configurations in either alloy or ceramic sheath materials, the A²™ is designed to meet most industrial atmosphere measurement applications over a wide range of operating temperatures.


United Process Controls stocks a wide variety of accessories for the A²™ including:

  • Probe Reference Air System
  • Probe Conditioning System (Burnout Air)
  • Probe Sampling Systems
  • Probe 330RA high temperature Mounting Flanges and Hardware
  • Ceramic Reheat Well
  • Shim Stock Testing Hardware (Holder, Shims, Port)