the trim panel and that the invention can be practiced with any conventional manufacturing process such as injection molding casting or the like referring now to fig3 and 4 another aspect of the cassette 10 of the invention is that the combination of the frame member 12 and the layer 46 of material may be designed to form a shear plane 48 at the interface between the frame member 12 and the layer 46 of material the purpose of the shear plane 48 is to assist in severing the layer 46 upon deployment of the airbag thereby eliminating or reducing the need for supplemental pre weakening of the layer 46 of material one way of forming the shear plane 48 is by using non compatible molding materials for the frame member 12 and the layer 46 of material another way of forming the shear plane 48 is by using compatible molding materials but forming an incomplete bond between the molding materials by selectively determining the relative bond strength between the frame member 12 and the layer 46 of material the shear plane 48 will cause the layer 46 of material to tear at the interface between the frame member 12 and the layer 46 of material when a shear force is.