Effective temperature-gravity diagram for sdBs produced in our study. For clarity, only the He-core burning phase is presented here. The solid lines show those from degenerate He cores before its ignition (), and the dashed lines show those from non-degenerate He cores (). Different colors represent different donor masses as indicated in the figure. The age differences between adjacent crosses are 2.5 × 10⁷ yr for each evolutionary track. The dots show known hot subdwarfs (Geier et al. 2017b).