A tool for demounting a first and second bead of a tire mounted on a rim, the tool comprising a handle having a first end for disengaging a first tire bead from a rim and a second opposite end for disengaging a second tire bead from the rim. An electro-mechanical device, includes a structure having a major horizontal surface and a channel formed therein. Alternatively, the above-mentioned separator plates are formed of a metal and a coat having resistance to oxidation and have roughened surfaces with recessions and protrusions, and portions of a top surface of the protruding portions, which lack the coat, are electrically connected to an electrode. Methods for using the tools and the tibial components are also disclosed. The silicon nitride film has a function to fill a hole or holes and suppress immersion of moisture from outside to the semiconductor device embedded with pressure sensor.