Molecular Characterization: S protein RBD(G339D, S371F, S373P, S375F, T376A, D405N, R408S, K417N,N440K, S477N, T478K, E484A, Q493R, Q498R, N501Y, Y505H)(Arg319-Phe541) hFc(Glu99-Ala330)Molecular weight: The protein has a predicted molecular mass of 51.4