A dressing having a flexible sleeve shaped to accommodate a substantially cylindrical body or plant portion, the sleeve having a lining which is substantially non-adherent to the body or plant part being bandaged and having a peripheral securement means which attaches two peripheral portions to each other without those portions being circumferentially adhered to the sleeve portion. The comb-shaped electrode excites a Lamb wave as a main wave. Applications in telecommunications backup, transportation, and military defense are contemplated. Other embodiments are disclosed herein. The system may also include infrared receivers for receiving infrared command signals from an infrared transmitter.