Oxygen analyzers and replacement O2 sensors by Applied Sensing Technologies, Inc. AST, covers a wide range of Galvanic type PPM Oxygen Sensors and % Oxygen Sensors for measuring oxygen concentration in a gas mixture from low PPM O2 up to 100% O2. these sensors are specific to oxygen. Oxygen analyzers and replacement O2 sensors offered by AST are excellent choice to measure oxygen in a variety of gas mixtures. The SRX and SRZ series Industrial PPM O2 sensors are drop-in replacement to Teledyne Class B-2C, B-2CXL, B-1, B-3, C-3, Class A-2C, A-5, GE Panametrics OX-1, OX-2, AII Model PSR-12-223, GPR-12-333, XLT-12-333, XLT-12-123 and XLT-12-333, GPR-11-32-RTS, GPR-11-60-RTS, GPR-11-120-RTS, GPR-11-120-4, GPR-12-100-M, XLT-12-100-M. AST SRX and SRZ series industrial % O2 sensors are drop-in replacement to Teledyne Class B-1, B-1C, B-3, C-3, A-5, AII Model PSR-11-21, XLT-11-15, GPR-11-32RTS, GPR-11-60RTS, GPR-120-4, GPR-11-120-RTS, AII-11-75D, AII-11-75-D-PO2, AII-11-60, GE Panametrics OX-3, OX-4, City MOX-1, MOX-2, MOX-3, MOX-4, ENVITEC OOM201, OOM202, KRANZ MK50212, MK50203, MK50204