  We show that the frame of the Kerr spinning particle consists of two
topologically coupled strings. One of them is the Kerr singular ring
representing a string with an orientifold world-sheet. It has electromagnetic
excitations (traveling waves), which corresponds to the old model of the Kerr's
microgeon. The excitations induce the appearance of the extra axial string
which is topologically coupled to the Kerr circular string and is a carrier of
pp-waves and fermionic zero modes. This string can be described by the Witten
field model for superconducting strings.
