AGB evolution of the main physical and chemical properties of the model stars with a solar metallicity with an initial mass of 4 M_⊙ (blue lines), 5 M_⊙ (red), and 6 M_⊙ (black), as a function of time, counted since the beginning of the AGB phase. The behaviour of luminosity (top left panel), mass-loss rate (top right), pulsation period (bottom left), surface ¹²C/¹³C (bottom right) are shown. The shadings in the bottom left panel indicate the range of values of the pulsation periods taken from the literature of: OH 30.1−0.7 (grey), 127.8−0.0 and OH 26.5+0.6 (yellow), and RAFGL 5379 (magenta).