double flowrate 3L oxygen concentrator , 1.purity indicator can be installed, 2.pressure alarm system, CE certified double flowrate 3L oxygen concentrator ,Specification: oxygen flow ratepurityvoltage frequenceoutlet pressuresound levelpowerweightdimensionother functions1-3L/min93+/-3%220V/50Hz0.04-0.06MPa<50dB(A)380W25Kg440*370*7501, .2,purity indicator can be installed.3, .CE certified double ...