Whether you’re protecting general workers or responders in industries includingpetrochemical, steel, or utilities, the Honeywell BW™ Flex Series delivers what youneed in an easy to use serviceable package. Sensor 1: %LEL (combustibles), catalytic, unfiltered Sensor 2: None (dummy sensor) Sensor 3: COSH (carbon monoxide+hydrogen sulphide) digital Sensor 4: CO (carbon monoxide) inflow Housing: Yellow housing Region: China Mining Approval