An airbag includes a first side panel, a second side panel, a middle panel, and at least one extension. In the inflated position, the first side panel and the second side panel are spaced from each other by the middle panel, the middle panel having a top and a bottom, and a centerline between the first and the second side panels. The at least one extension is connected to at least one of the first side panel and the bottom of the middle panel, and is extendable in a direction away from the top of the middle panel in a deployed position.