Altair® 4XR Multigas Detector with North American Charger, 4 Gas, LEL - CO - H2S -O2Features sensors for LEL, O, CO, and HS LC (low concentration) Sense gas 2 times faster than the industry average with XCell sensors Provides real time incident awareness to team members, supervisors, safety managers and others when paired with the MSA Altair Connect app via a Bluetooth wireless connection Survives 25 drops from 4 feet, and can survive an incidental 25 foot (7. 5 m) drop onto concrete Confirm compliance quickly with the bump LED & on