This machine safely boosts oxygen gas up to 350 bar and is used to fill oxygen cylinders efficiently and safely. It can also be used to boost gas pressures and mix gases for applications in aviation, aerospace, and diving industries including in-flight oxygen, SCUBA, and rebreathers. The machine is integrated according to safety standards and uses cleaned components and gauges to handle oxygen at pressures up to 4500 psi while being powered by a 5 bar air drive.