O2 CONCENTRATION：93%±3%. O2 FLOW RATE：0.5-5L/Min (O2 Concentration of 93%±3% Constantly Maintained, Regardless of The Flow Rate, Whether 0.5L/Min or 5L/Min). ALARM (SOUND + INDICATOR LIGHTS)：Power Failure, High&Low Pressure, Low O2 Concentration (≤85%±3%).
eBay
Comprehensive Alarm System: Alarm for power failure, irregular pressure, and low O2 levels. O2 FLOW RATE：0.5-5L/Min (O2 Concentration of 93%±3% Constantly Maintained, Regardless of The Flow Rate, Whether 0.5L/Min or 5L/Min).
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Portable Oxygen Concentrator Battery O2 Machine Household Oxygen Generator Car Oxygen Concentrator
Aliexpress UK
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Aliexpress UK