Airbag module

The fasteners (20, 22) for securing the cover (14) to the module casing (12) are provided on side walls (15) of the cover and casing. The fasteners are connected together by moving the cover and casing relative to each other in a direction at right angles to the airbag escape direction (R), in order to prevent the cover becoming detached from the casing in the airbag escape direction.