A bi-directional switch circuit includes a pair of N-type MOS devices connected in series with a common source terminal, and a pair of P-type MOS devices connected in series with a common source terminal. In one embodiment, different silicon nitride thicknesses are formed above gate electrodes followed by nitride etching to form spacers. The information terminal apparatus is arranged by a personal computer which supplies image data to the projector, and personal computers which are connected to this personal computer by a wireless manner. User’s feet are urged against the top of handles for exercising up and down repeatedly.