A model of the electrode I electrolyte interface in the presence of specific anion adsorption is presented. A classical division of the interface into inner and diffuse layers is adopted. The surface solution is composed of partially solvated anions and solvent molecules. The anions and solvent molecules are treated as hard spheres with embedded point charges and point dipoles respectively. Partial charge transfer from the adsorbed anions to the electrode surface is assumed. The electrostatic interactions of anions with the electrode charge, other adsorbed anions and electric dipoles of solvent molecules are considered. Also the non-electrostatic (specific) interactions between anions and the electrode surface are taken into account. The properties of solvent molecules are calculated from the model elaborated earlier. The composition of the inner layer is obtained by minimizing the Gibbs energy of transition of anions and solvent molecules from the bulk to the inner layer. The influence of the bulk anion concentration, the energy of the specific anion interactions, the anion diameter, its solvation and the charge transfer effect on the composition of the inner layer and the differential electrical capacity of the interface is discussed.