Evolutionary tracks of the produced sdB stars from the star with an initial mass of 1.0 M_⊙ and a core mass of 0.446 M_⊙. The sdB mass, M_sdB, is artificially set to be equal to 0.452, 0.454, ..., 0.472 and 0.474 M_⊙ (in steps of 0.002 M_⊙). The products crowd at the hottest end of EHB for M_sdB = 0.452−0.466 M_⊙ (located in the shaded region between the lowest two solid lines), and spread throughout the canonical sdB region when M_sdB ≥ 0.468 M_⊙ (from bottom to top, M_sdB = 0.468,0.470,0.472, and 0.474 M_⊙). The red dashed line shows the standard model (M_sdB = 0.453 M_⊙). SdBs with short orbital periods from Maxted et al. (2001) and Kupfer et al. (2015) are presented in the figure for comparison. The grey lines are the tracks during helium flashes before stable He-core burning.