Compact, rugged in design and fully serviceable with simple 1-button operation Available sensors: 02, CO, h2S, PH3 and NH3. Three highly-visible, chasing yellow and red alarm LEDs plus vibration. Max, STEL and TWA readings are accessible by pressing the MODE button. Data loggining included. Continuous real-time gas readings. Includes black-box recorder and event logger (100 events). Meets IP66/IP67 ingress protection. Compatible with the IQ Express Docking Station C-UL-US. Classified for Class I, Div. I, Groups A, B, C and D T4; Class II, Div. I, Groups E, F and G.