Alphasense O2-A2 Oxygen Sensor Compatible with BW Technologies GasAlert MicroClip XT PERFORMANCE Output μA @ 20.9% O2 80 to 120 Response time t90 (s) from 20.9% to 0% O2 <15 Zero current μA in N2 <2 Linearity % O2 deviation @ 10% O2 0.6 O2-A2 Oxygen Sensor for BW Technologies Gas Detectors One Replacement Oxygen Sensor compatible with following BW models: BW Technologies GasAlert MicroClip XT BW Technologies GasAlert Max XT-II BW Technologies GasAlert Micro BW Technologies GasAlert Micro 5 BW Technologies GasAlert Quattro BW Technologies GasAlert Max Oxygen sensor needs to be replaced when ERR appears on the position of the O2 reading Brand new, sealed, latest manufactured by Alphasense.