An electronic media edge defect detector in one form has plural light sources and detectors arranged to direct and receive deflected light from the side edge margins and outer edge margins of the electronic media. In the disclosed plough, each plough body is a uniform component and has the shape of a tube that is bisected in longitudinal direction in a vertical plane and has slanted edges at its front and rear, wherein the longitudinal axes of the plough bodies are each aligned parallel to each other and at an angle with respect to the working direction of the plough. In another aspect of the inventive concept, a mobile station uses the equipment identity information of a location server to select the best protocol to use for LCS communication. The protective coverings are provided with frictional means for engaging the inner wall of the tire to prevent circumferential or lateral displacement of the tire carcass during rotation of the wheel.