The DC adapter is designed to power your Inogen G3 or G4 portable oxygen concentrator. You can use it to power your concentrator from an automobile, RV, boat, or anything with a cigarette lighter style plug. This adapter comes with all new Inogen concentrators. This is a replacement cord.
Fun fact: If you’re a camper, or worried about power outages, this cord can be used to connect to some generators and battery style power sources.