Coverage of our grid of  FASTWIND models in the sHRD (Langer & Kudritzki 2014). The evolutionary tracks (dashed), location of the ZAMS (solid gray), and isochrones (dotted) for τ = 1, 2, 3, and 4 Myr as resulting from the nonrotating solar metallicity models by Ekström et al. (2012) and Georgy et al. (2013) are shown for reference. The dotted diagonal lines (following the points) are isocontours of constant gravity. Crosses map models with EW(He Iλ4471) < 0.15 Å. The solid black line separates these models from those for which the He Iλ4471 line has a larger EW (representedby dots). The inset in the bottom left corner depicts three He Iλ4471 line profiles corresponding to the models highlighted in the figure with large colored circles (see text for details of the analysis).