Another particular aspect of the invention is in providing a diffuser over the outlet orifice
, and advantageously the diffuser is formed of a metal stamping part fitted snugly against the outlet orifice and deformable away from the outlet orifice by the inflation gasses exiting the inflator housing. The deformable diffuser provides a more compact inflator prior to operation, and also absorbs some of the energy from the initial surge of gas to provide a controlled initial inflation of the airbag.