Magnetic bodies for reducing electromagnetic wave noises are mounted to a battery voltage supplying terminal for supplying of an electric source power for the operation of circuits to an IC chip of a regulator or an internal electric source line for connection of the terminal to the regulator chip. The spool valve includes a cylindrical sleeve and a spool. The insertion hole has a widened portion that is inclined in such a manner that a distance between an opening on the pressing portion side, the opening positioned on a screw-hole-forming-portion end surface, and the pressing portion gradually becomes larger toward the slidable-contact portion side. Optical fiber connectors are inserted into the opposite end portions of the cylindrical portion and brought into abutting contact with each other in an axially intermediate portion of the cylindrical portion in a manner such that misalignment in axis of the optical fibers of the connectors is minimized. The capture mass comprises molybdenum in a sulphurized form, nickel in a sulphurized form and at least one porous support selected from the group constituted by aluminas, silica, silica-aluminas, titanium oxide and magnesium oxide.