Ejected nickel mass, M_Ni, (a) and squared SN velocity, (v_Fe, 50)², (b) as a function of plateau luminosity, L_p, 50, of our SN IIP models. The different symbols are for single stars, and Case A, B, and C accretors with the accreted mass fraction, f_acc, indicated by the colours. Linear fits to the data of the single-star models (dashed black lines) are shown to guide the eye. Moreover, linear fits to the data of the accretor models with the same slopes as those for the single-star models are provided to indicate possible systematic differences (dotted black lines). Black crosses indicate models with likely significant LBV mass loss.