An airbag module including an inflatable airbag and an inflator. The airbag is formed by a main panel and a pair of side panels and deploys into a position to contact the occupant. The airbag includes a tether connected to the main panel at one end and is anchored proximate to the inflator at the other end. Prior to inflation, the airbag includes a pre-folded portion adjacent to the tether. The airbag is configured so that during an initial stage of the inflation process the tether is fully extended and the pre-folded portion remains folded and during a final stage of the inflation process the tether separates into at least two portions thereby allowing the pre-folded portion to unfold and the airbag to fully deploy.