an air cushion restraint system providing enhancements in the strength of the attachment between an air bag and associated support structure and further providing improvements in the fabrication and assembly of such systems . acrs systems in accordance with this invention incorporate an air bag with a retainer ring member which reinforces the inflation or mounting opening which is provided to enable inflation gases to be vented into the bag and to mount the bag to the associated vehicle structure . the retainer ring is sewn directly to the air bag at the inflation opening and is preferably made of a polymeric material . in a preferred embodiment the retainer ring features projecting post members which enter and engage with apertures in a corresponding mounting structure to prevent the air bag from pulling away from the attachment structures during depolyment