The simplest common mode filter involves the placement of a dual winding magnetic in the line and neutral path and capacitors between line and neutral and ground, as shown in the above sketch. When high-frequency common mode noise tries to circulate through the system it comes up against the high impedance of the common mode inductor and therefore takes the low impedance path through the capacitors. The common mode choke effectively blocks the high frequency noise from moving through the system. It should be noted that because the common mode inductor sees both the line and neutral currents, but in opposite directions, there is essentially no net DC offset within the common mode choke.