Abstract: A stabilized saturated reactor comprising a solid toroidal core of magnetic material. The core has at least one end face provided with plural circumferentially spaced slots. Each slot extends in a substantially radial plane with respect to the central axis of the core. Each slot has a width substantially less than the cross-sectional dimensions of the core. The core may have a second end face which is provided with plural slots staggered circumferentially in relation to the slots in the other end face to simulate a linear reactor. The core, with both end faces slotted, may be combined under a common winding with an unslotted saturated toroidal core spaced therefrom to simulate the stabilized saturated reactor core having only one slotted end face.