This fireplace bridging tool is easy to use to install tile across fireplace headers. It is constructed of durable PVC, to insure that your bridging tool will never warp or splinter. All you need to do after installing hearth and fireplace side tiles is position the tool centered on the fireplace opening. Next adjust the legs so that the bridging header brace is level from one side of the fireplace to the other. Then tighten wing nuts/washers to anchor the leg adjustment setting. Then go ahead and set your tile across the header using the brace for support.