Requirements for synchronizing the white dwarf spin as a function of the magnetic field of the white dwarf and the mass transfer rate from the donor. The white dwarf spins synchronously if B exceeds the limit shown by the dash-dotted line. Above the solid line the accretion disk is absent since the pressure of the equatorial magnetic field exceeds the free-fall ram pressure of the accretion stream. The shaded area corresponds to the mass accretion rates determined for V479 And from X-ray luminosity. Isolines of equal velocity calculated for the treading region, i.e., the highest velocity reached by the stream of matter from the donor star to the treading radius where the magnetosphere of white dwarf captures matter and diverts it to the white dwarf surface are shown by dashes. This is the radial velocity of the emission line components that are expected to be emitted if the stream and, particularly, the coupling region are ionized.