Gas Detector Sensor, Gas Detected Carbon Monoxide, Hydrogen Sulfide, Measurement Range 0 to 100 Percent, Compatible Detector Model/Series ALTAIR 4XR, ALTAIR 5X, Compatible Detector Grainger Part Number 45KE54, 45KE55, 481P57, Sensor Type Catalytic, For Detector Type Portable, T90 Response Time 15 sec, Compatible Detector Manufacturer Part Number 10107602, 10110443, 10110444, Sensor Life 4 yr, Series ALTAIR 4XR, ALTAIR 5X, Features Quick Response Time, Resolution 1 Percent LEL