Abstract: The invention provides a pad fitting device for a wind musical instrument key. In this device, the center of the pad (2) is connected to the center of the bottom of the cup (3) by a spherical hinge (5, 6) allowing a free universal angular movement of pad (2) without rotation, so that the pad may assume any slanted position with respect to the cup (3) so as to be applied freely and uniformly at all points of the chimney (1) which it is to close, thus ensuring sealing even in the case of deformation of the key or of the pad (2). Furthermore, since the pad (2) is resiliently snap fitted, it may be replaced instantaneously.