Abundances of several elements in mass fraction in the inner core of three models with different primordial MS masses and different metallicities at the moment of envelope ejection. The solid, dotted, dashed and dot-dashed lines represent hydrogen, helium, carbon, and oxygen abundance, respectively. Top: Z = 0.001 and M_i = 3.51; middle: Z = 0.02 and M_i = 4.52; bottom: Z = 0.06 and M_i = 4.32.