A resilient stopper component (20) is provided with a bottom surface portion (48) that is mounted, via an inner bracket (22), at one of a vibration-generating portion or a vibration-receiving portion, and that has a communicating hole (48A) provided in a first mounting component (11) that is provided with a cylindrical component (24) inside which the inner bracket (22) is inserted, with the cylindrical component (24) being inserted through the communicating hole (48A), is also provided with an enclosing portion (50) that is formed extending upright from the bottom surface portion (48) so as to be able to enclose the cylindrical component (24), in which an aperture portion (58) that forms an aperture for inserting the inner bracket (22) into the cylindrical component (24) is formed so as to be in communication with the communicating hole (48A), and limits a displacement amount of the first mounting component (11).