Current stellar age versus mass for the SB1 luminosity class III–V primaries (black circles, error bars in grey to aid legibility) and the SB2 primaries (red circles). Also shown are the loci of the 25% (black dashed line) and 50% (red dashed line) of main sequence lifetime ages as derived from the models of Brott et al. (2011). SB1 systems that are deemed synchronised (Table 5) are indicated as filled circles. All SB1 parameters were calculated assuming 0% flux contribution of the secondary, however adopting a 20% contribution only shifts points on average by approximately −0.5 M_⊙ and +0.2 Myr.