Calculated spectral energy distributions (Eddington flux in cgs units) versus wavelength of the 1000   M_⊙ sequence of the VMS model grid stars. The effective temperature of the models in the first row is equal to T_eff = 30   000   K, in the second row to T_eff = 45   000   K, and in the third row to T_eff = 65   000   K. For the models shown in the left column solar abundances have been assumed. This is also the case for the models in the middle column, but for which the atmospheric hydrogen abundance has been additionally reduced to X = 0.4. For the models shown in the right column, finally, the metallicity has been scaled down to 1/20 of the solar value. As the figures convincingly show, the metallicity Z and the atmospheric hydrogen abundance X have an enormous influence on the behavior of the spectral energy distributions (mainly due to the corresponding changes of the hydrodynamic structures).