The bulge design of side rails is to enhance hand feeling and improve your gaming experience. These back pannels will look great on your Xbox One controller.Make your Xbox One controller stand out from the crowd. Easy installation.No opening shell or any complicated action is needed to install these pannels. Safety,non-toxic and odourless paint. Orange-peel finish paint.Granule bulge design. Compatible with any Xbox One Controller Package Included: 1*Right Back Panel 1*Left Back Panel