Model predictions for the chirp mass M_chirp, effective inspiral spin parameter χ_eff, cosmological redshift of merger z_merger, BBH merger timescale T_merger, metallicity Z and the binary mass ratio q distributions of binary black holes observables at design sensitivity. Lighter colors represent larger contour levels of 68, 95 and 99%. We arbitrarily divide the two dimensional histogram M_chirp vs. χ_eff with red lines into three regions at χ_eff = 0.1 and M_chirp = 15 M_⊙. Region-A contains 80% of the events, 10% are in Region-B and 10% are in Region-C. For illustrative purposes, all histograms are plotted with a smoothing scale of 0.8 bins with the exception of z_formation vs. χ_eff, z_formation vs. z_merger, q vs. χ_eff that have no smoothing.