  We study the states of 3D-electron gas in non-homogeneous magnetic field. It
is supposed that the step of magnetic field, at which field changes its sign,
lies on the cylindrical surface. The eigen value problem is solved for are
different parameters of the system. The equilibrium statistics in the limit of
large quantum lifetime are considered as well. It is predicted that the system
characterized by quasi-zero-dimensional spectra with large density of states;
snakes orbits lead to the effective charge transfer; an appearance of the
magnetic field step strongly modify the coordinate dependence of carriers
concentration.
