Mass over time for candidate primary component of F2, from latest Geneva evolutionary models with Z = 0.014. Initial masses are shown (in solar masses) next to each track on the left; for the 60, 85, and 120 M_⊙ tracks, bothrotating and non-rotating models are shown (the rotating models are in red, yellow, and cyan respectively, and have greater duration than the corresponding non-rotating versions in black, orange and green); for higher initial masses, only non-rotating models are available. Each track follows the life of a star to the end of the C burning stage (dotted lines); WNL phases, as defined in Georgy et al. (2012), are shown in thicker solid lines.