My talk will be about 'The return current effect on the differential and mean spectra of electron beams and their resulting hard X-ray emission'. I am planning to present analytical and numerical simulations of the distribution function, differential and mean electron spectra of precipitating and returning electrons for the accepted hydrodynamic models a flaring atmosphere. These will include : 1) pure collisional model as a benchmark; 2) simple case including collisions and return current for two options (mu=1 and mu=-1); 3) more complicated case with anisotropic scattering.explaining the calculated maxima in energy and pitch angles in the returning beam distributions. We also provide the explanation of a maximum in mean electron flux distributions and consequently, a dip at lower energies and relate it to the other model parameters. Also we propose the semi-analytical way to include the return current effect into the inversion problem using the energy magnitude where the observed photon spectrum have a broken index.