A planarized cover layer structure of a flexible circuit board includes an insulation layer bonded through a first adhesive layer to a surface of each one of conductive signal lines laid on a substrate of a flexible circuit board. The display stand housing can be configured to hold one or more graphic panels. A rotational shaft includes a timing member, a counterclockwise rotational stop and a clockwise rotational stop. The other end also receives a fastener, such as a bolt, which secures the material or the track to the end of the device, the end of the device being substantially flush with the exterior veneer surface. The annular lip has a stem and a tip and is attached to the seal body in a manner allowing deflection of the lip relative to the seal body. The thin-walled portions each have an inner surface that is outwardly recessed in an angular range including the intersection of the inner surface with a reference line, thereby securing sufficient air pocket size of the spark plug.