sentence: these materials include : low-density flexible foam used in upholstery , bedding , and automotive and truck seating low-density rigid foam used for thermal insulation and rtm cores soft solid elastomers used for gel pads and print rollers low density elastomers used in footwear hard solid plastics used as electronic instrument bezels and structural parts flexible plastics used as straps and bands polyurethane foam is widely used in high resiliency flexible foam seating , rigid foam insulation panels , microcellular foam seal and gasket , durable elastomeric wheels and tires , automotive suspension bushings , electrical potting compounds , seals , gaskets , carpet underlay , and hard plastic parts ( such as for electronic instruments ) .