MSA ALTAIR® Single-Gas Detector, Hydrogen Sulfide (H2S), Button® Cell Toxic Gas Sensor (454-10092521) EachFeatures: Automatically records the last 25 alarm test events and can communicate data by connecting to MSA Link via built in IR communication port Dust and water protection rated IP67 Patented electrochemical sensors and MSA built button sensors Rated to IP67 protection levels for dust water ingress Rubberized armor housing and one button operation for maximum durability and simplicity Stainless steel and solid electrolyte construction virtually