A vibrating apparatus comprising: a housing including at least one wall provided with at least one aperture having a centre axis, a peripheral flange which protrudes from said wall at said aperture and is configured to cooperate with a covering , wherein the peripheral flange includes a plane surface for abutment of the covering , said plane surface extending in a plane, said centre axis being perpendicular to said plane, wherein a) said peripheral flange is formed as an integral part of said wall and from the wall material itself, b) the peripheral flange comprising an inclined portion that extends toward an exterior environment thereby creating a distance or an offset to the wall , whereby said plane surface of the peripheral flange is offset from the wall in a direction along the centre axis of the aperture, the plane surface having a width defined as the distance between an inner edge of the plane surface and a transition to the inclined portion , c) said aperture has a minimum opening or diameter, measured as the distance from one point at the inner edge of the plane surface on the peripheral flange through the centre point of the aperture to another point on the peripheral flange, which is opposite the first point, the inner edge being the edge nearest to the centre point of the aperture . a housing including at least one wall provided with at least one aperture having a centre axis, a peripheral flange which protrudes from said wall at said aperture and is configured to cooperate with a covering , wherein the peripheral flange includes a plane surface for abutment of the covering , said plane surface extending in a plane, said centre axis being perpendicular to said plane, wherein a) said peripheral flange is formed as an integral part of said wall and from the wall material itself, b) the peripheral flange comprising an inclined portion that extends toward an exterior environment thereby creating a distance or an offset to the wall , whereby said plane surface of the peripheral flange is offset from the wall in a direction along the centre axis of the aperture, the plane surface having a width defined as the distance between an inner edge of the plane surface and a transition to the inclined portion , c) said aperture has a minimum opening or diameter, measured as the distance from one point at the inner edge of the plane surface on the peripheral flange through the centre point of the aperture to another point on the peripheral flange, which is opposite the first point, the inner edge being the edge nearest to the centre point of the aperture . a) said peripheral flange is formed as an integral part of said wall and from the wall material itself, b) the peripheral flange comprising an inclined portion that extends toward an exterior environment thereby creating a distance or an offset to the wall , whereby said plane surface of the peripheral flange is offset from the wall in a direction along the centre axis of the aperture, the plane surface having a width defined as the distance between an inner edge of the plane surface and a transition to the inclined portion , c) said aperture has a minimum opening or diameter, measured as the distance from one point at the inner edge of the plane surface on the peripheral flange through the centre point of the aperture to another point on the peripheral flange, which is opposite the first point, the inner edge being the edge nearest to the centre point of the aperture . <EOS>