Abstract: The electromagnet, at least comprising a magnet coil wound onto a coil core, a housing, a pole core, an armature, an armature rod and a yoke, should have a very low hysteresis of the force with a variable stroke at low manufacturing costs. The coil core is manufactured by jointly overmolding or overcasting the yoke, the pole core and the core flange with a plastic mass, wherein the axial intermediate space between the yoke and the pole core (4) is also filled with the plastic mass. Electromagnets of the described type are used for actuating fluid valves or couplings, preferentially in motor vehicles or in mobile working machines.