Comparison of the maximum convective velocities for different convection models as a function of stellar luminosity. For the Kuhfuß model, the isotropic convective velocity, v_c,iso, is plotted. The dotted lines indicate a linear fit to the logarithmic data. We note that the data of the 1- and 3-equation Kuhfuß models (red and blue points, respectively) are largely overlapping, as are the black and yellow dots.