plate 3 in the embodiment according to fig4 a strip shaped coating 15 is again present at the rear edge 16 of the wind deflector plate 3 on the remaining external surface of the wind deflector plate 3 individual coating region 17 are applied at intervals the arrangement of these regions advantageously being staggered the brush like coating applied by electrostatic fibre deposition and constituted of synthetic fibre strands of approximately 1 to 2 mm in length ensures that when the wind deflector pltat 3 is raised the air flow striking the wind deflector plate during travel is greatly retarded in the boundary layer zone with the result that the abrupt formation of aturbulent zone immediately adjacent the rear edge 16 of the wind deflector plate 3 is considerably disrupted measurements have shown that the noise level in the interior of an automobile when the sliding roof 2 is opened is considerably reduced if instead of an uncoated wind deflector plate aplate coated according to this invention is used these measurements are given in the following table the measurements were carried out for five different speeds one measuring point being located on the right hand forward seat r and a further measuring point being located in the rear region of the automobile interior h the readings were recorded in db a for a speed of v 180 km h no measurement is available for the rear measuring point in the case of the coated construction of the wind deflector plate as the table shows at all speeds considerably.