Manufactured by Inogen, the Inogen One G3 system is one of the lightest and smallest portable machines on the market weighing 5.25 pounds (including the standard battery and carry case), 3.5 pounds by itself, 4.8 pounds for device and battery. The design allows the freedom and independence that are missing with traditional devices. This portable Inogen machine can be used for stationary or portable oxygen for traveling. The Inogen G3 Concentrator can be powered from three separate power sources: a rechargeable lithium-ion battery, AC power, or DC power. The AC power supply is auto-sensing, allowing worldwide use. The oxygen flow is a pulse dose with five settings from 1 to 5. Oxygen concentration levels are from 87 to 96 percent with a maximum flow of 840 mL. Noise output is a modest 39 decibels. It is capable of continued use both day and night while on extended vacations.