One- to five-sensor gas detector. Real-time wireless data transmission with built-in RF transceiver. View real-time sensor data and alarm status at headquarters or command center. ProRAE remote software simultaneously controls and displays readings for up to 32 remote detectors. Toxic sensor socket accepts CO, H2S, SO2, NO, NO2, Cl2, HCN, NH3, or PH3 sensors. 24 hours continuous operation with a built-in Li-ion battery. 24x7 continuous operation when plugged into wall charger. Interchangeable Li-ion or alkaline battery pack.