Specifications: Oxygen flow(L/min):0～4 Oxygen concentration(%):≥90% Oxygen delivery pressure(Mpa):0.03～0.07 Noise dB(A):≤52 Atomizing pellet(m1/min):≥0.5 Size(mm):488(Height)?358(width)?318(depth) Net weight(kg):32 Power: AC 220±10? 50±1Hz Power consumption:≤500W Electric classification : Class II Grade B Power failure alarm: Yes High & low pressure alarm: No