The present invention relates to a stabilizing center core for stabilizing a coil of duct or cable. The stabilizing center core comprises a center tube having a first and a second end. A first plate element is arranged at the first end of the center tube, and a second plate element is arranged at the second end of the center tube. The center core further comprises at least three third plate elements extending between the first plate element and the second plate element and arranged at angular distances around a circumference of the center tube, whereby a duct or cable that is wound around the stabilizing center core is supported by the third plate elements.