T_eff−log g-diagram for the entire sample (not RV-variable) under study. The helium main sequence (HeMS) and the EHB band (limited by the zero-age EHB, ZAEHB, and the terminal-age EHB, TAEHB) are superimposed with EHB evolutionary tracks for solar metallicity taken from Dorman et al. (1993) labelled with their masses. Open circles mark objects where only upper limits could be derived for v_rotsini, filled circles objects with significant v_rotsini. The size of the symbols scales with the value of v_rotsini.