BW Flex-i – %LEL(F) O2 H2S CO (Filtered Catalytic LEL), BW Flex-i – %LEL(IR) O2 H2S CO, BW Flex-i – %LEL(IR) O2 H2S SO2, BW Flex-i %LEL(F) O2 H2S SO2 (Filtered Catalytic LEL), BW Flex-i %LEL(UF) O2 H2S CO (Unfiltered Catalytic LEL), BW Flex-i %LEL(UF) O2 H2S SO2 (Unfiltered Catalytic LEL)