Abstract: An actuator delivers mechanical vibrations to the body of a subject. The actuator includes a piezoelectric element, electrodes in electrical communication with an electrical source and the piezoelectric element to drive the piezoelectric element, a polymeric protective layer encapsulating the piezoelectric element and part of the electrodes, and an enclosure attached to the protective layer. The actuator includes a space between the protective layer and the enclosure allowing desired modes of vibration to develop across a surface of the protective layer that encapsulated the piezoelectric element. The actuator can include a skin attachment article that has a mounting pad for attaching to the skin of the subject and for attaching the actuator. The skin attachment article has a cover that overlies the actuator and the mounting pad when the article is attached to the skin of the subject.