Abstract: A valve is disclosed for an air-bag for use as a safety device in a motor vehicle. The valve comprises a fixed component (1) which has a mount such as a mounting flange (2) for mounting the fixed component (1) to an air-bag or gas generator housing. The fixed component (1) defines at least one aperture (5). The valve also incorporates a moveable component (6) which is configured to be slidingly engaged with the fixed component and which has at least one other aperture (11) formed therein. The two components (1), (6) have an initial position in which the aperture (5) in the fixed component is off-set from the or each aperture (11) in the moveable component. The moveable component is moveable relative to the fixed component to a position in which at least part of the or each aperture (11) formed in the moveable component (6) is co-aligned with the aperture (5) in the fixed component (1) so as to create a vent flow passage for gas from the interior of the air-bag or gas generator housing.