An inflatable cushion for a side of a vehicle is disclosed herein, the inflatable cushion having: a first cushion section formed from a first material, the first cushion section having a plurality of separate inflatable cells each of which having an inlet opening for receipt of an inflation gas; an internal passageway formed in the first cushion section, the internal passageway linking and fluidly coupling to each of the plurality of separate inflatable cells via the inlet opening of each of the plurality of separate inflatable cells; a diffuser member disposed in the internal passageway, the diffuser member being configured to supply the inflation gas to each of the plurality of separate inflatable cells, wherein the diffuser member consists essentially of a non-rigid fabric member formed from a permeable material, the non-rigid fabric member is independent of the first material used to form the first cushion section and the permeable material of the non-rigid fabric member is the main source of fluid flow into each inlet opening of each of the plurality of separate inflatable cells such that the inflation gas must pass through the permeable material; and means for restricting fluid flow between the plurality of inflatable cells by limiting fluid flow between an exterior portion of the diffuser member and an interior surface of the internal passageway proximate to an edge of the inlet openings of the plurality of inflatable cells.