SMT channel becoming ineffective at high metallicity because of the combined effect of the separation limit in SMT evolution and orbital widening via Wolf-Rayet winds. We plot the outcome of binary MESA models at different metallicities, marking BBH mergers with stars. The first BH mass is M_BH; 1 = 10 M_⊙ and we assume the fiducial AM loss for SMT (γ = γ_BH). Color indicates the final fate, same as Fig. D.1. The blue line marks the boundary between MS and post-MS donors.