Batteries are not included ( should use 2 AAA).
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Portable Oxygen Concentrator Battery O2 Machine Household Oxygen Generator Car Oxygen Concentrator
Aliexpress UK
Portable Oxygen Concentrator Generator 24hours Continuous Room Oxygen Chamber 5L Oxygen Bar
Aliexpress UK
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
Ideal for a wide range of users. Featuring a premium molecular sieve, it ensures your every breath is clean and purified. So you can enjoy an oxygen support wherever you are. When connected to a power cord, the device can run longer.
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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3L Oxygen machine for home use with touch button.
eBay
(Adjustable alarm value, alarm tone up to 80 decibels.). 66.35 95.8 52mm / 2.6 3.8 2in Weight: approx. We will respond as soon as possible and help you resolve them! This restriction also applies to a fault that has arisen as a result of improper repairs by a service partner authorized by us.
eBay
Ideal for a wide range of users. Featuring a premium molecular sieve, it ensures your every breath is clean and purified. So you can enjoy an oxygen support wherever you are. When connected to a power cord, the device can run longer.
eBay