PEM full name is Proton Exchange Membrane. Also called SPE technology ( solid polymer electrolyte). Through electrolysis pure water( no need to add chemicals) to produce high purity O2. O2 output purity could reach 99.999%, O2 output pressure is 0--4/7bar/0-10bar, output pressure is very stable. No fluctuation. With O2 output flow rate display, O2 output pressure display, Water level display. Our O2 generator also have several safety protection. Even customer forget adding water in time, whole O2 generator and inside cell will not working to protect. Also have anti high pressure protection. Mostly important, our cell quality average lifetime is 5 years. Much more durable to be used compared with other suppliers. As we already produced 17 years. With very reasonable cell structure and use Titanium 1 material as electrode, USA Dupont brand PEM membrane as key materials. This machine is light, high effective, energy saving and environmental protection. And world advanced patent right products. Model SPE-150O2 SPE-300O2 SPE-600O2 SPE-1000O2 SPE-1500O2 O2 Flow ( ml/min ) 0--150 0--300 0--600 0--1000 0--1500 O2 Output Purity 99.999% O2 Output Pressure Standard machine: 0.2---0.4MPa High pressure machine: 0--0.7MPa or 0--1MPa ( Under Stable Pressure ) Input Power( W )