Inogen At Home Oxygen Concentrator Air Inlet Filter – Overview This is the Inlet Filter for the Inogen At Home Stationary Concentrator. This is a filter designed to protect your concentrator from airborne contaminants. The filter is located at the back of the concentrator, near the handle. It can be removed by sliding it up off of the concentrator. The Inogen At Home Stationary Concentrator will display a priority error stating “Service Needed” indicating when the filter needs to be replaced. * The filter is tightly seated onto the concentrator. It may require a tool for the removal and insertion of a new filter. Inogen At Home Air Inlet Filter – Features Protects your oxygen concentrator from contaminants in the ambient air. Can last for up to 5 years if properly maintained. Compatible with the Inogen at Home Stationary Concentrator.