Support plate with vibration filtering of an element to be supported, which extends parallel to a main plane orthogonal to an axial direction, such that: - an outer, peripheral, rigid, plate-shaped element is bounded by two large faces (2a, 2b) and has a through hole limited by an annular inner edge comprising at least one localized notch having a radial opening, a first and a second axial opening (9a, 9b) towards the respective large faces (2a, 2b), a peripheral edge extending in the axial direction having first and second edges (1, 1a, 1b) towards the respective first and second opening (9a, 9b), - an inner, median element in one piece and at least part of which is elastically deformable, of flat shape, is limited by two large surfaces (13a, 13b) and comprises an annular central core with a through passage limited by an outer edge, and at least one arm extended substantially radially with a terminal protuberance, - the inner element is housed in the hole while the protrusion is housed in the conjugated notch, in contact with its edge by shape complementarity, and the outer element and the inner element form an inseparable unit, - in conjunction with the outer element, a first outward axial locking means and a second outward axial locking means, located respectively towards the two large faces (2a, 2b), have respective active locking zones (28a, 28b) spaced in the axial direction by a distance corresponding to the thickness of the axial protuberance, - the active zones (28a, 28b) of the first locking means and the second locking means being, respectively, arranged, in the axial direction, in alignment with the first opening and the second opening of the notch, - once the protuberance is housed in the notch and in contact with its edge, the two large surfaces of the protuberance are blocked in the axial direction by the active zones (28a, 28b) of the blocking means (27a, 27b), characterized in that the projections on the main plane of the first blocking means and the second blocking means are at least partially offset from each other, more particularly totally or almost totally offset from each other, more especially spaced from each other. - an outer, peripheral, rigid, plate-shaped element is bounded by two large faces (2a, 2b) and has a through hole limited by an annular inner edge comprising at least one localized notch having a radial opening, a first and a second axial opening (9a, 9b) towards the respective large faces (2a, 2b), a peripheral edge extending in the axial direction having first and second edges (1, 1a, 1b) towards the respective first and second opening (9a, 9b), - an inner, median element in one piece and at least part of which is elastically deformable, of flat shape, is limited by two large surfaces (13a, 13b) and comprises an annular central core with a through passage limited by an outer edge, and at least one arm extended substantially radially with a terminal protuberance, - the inner element is housed in the hole while the protrusion is housed in the conjugated notch, in contact with its edge by shape complementarity, and the outer element and the inner element form an inseparable unit, - in conjunction with the outer element, a first outward axial locking means and a second outward axial locking means, located respectively towards the two large faces (2a, 2b), have respective active locking zones (28a, 28b) spaced in the axial direction by a distance corresponding to the thickness of the axial protuberance, - the active zones (28a, 28b) of the first locking means and the second locking means being, respectively, arranged, in the axial direction, in alignment with the first opening and the second opening of the notch, - once the protuberance is housed in the notch and in contact with its edge, the two large surfaces of the protuberance are blocked in the axial direction by the active zones (28a, 28b) of the blocking means (27a, 27b),