% O2 sensors – ventilators, these sensors are designed for measuring oxygen in breathing air equipment, respirators, ventilators, oxygen concentrators and for spot checking oxygen in O2 supply lines. AST offers replacement for R-22, PSR-11-39M, PSR-11-39M2, OOM201, OOM202, MOX-1, MOX-2, MOX-3, MOX-4, T-7, AII-11-60, PSR-11-75-KE4 and many other manufacturers sensors