Upper panel: P(ρ) profiles corresponding to the M(R) relations from the left panel of Fig. 1, with the SLy4 model denoted by a red solid line, Model1 by a green dashed line, and Model2 by a blue dash-dotted line. Thick semi-transparent lines denote P(ρ) ranges for the two components of the GW170817 binary neutron star system (Abbott et al. 2017a, with mass estimates using the low-spin priors). We also plot the pressure difference between the SLy4 model and Model1 (dashed green line, middle panel) and Model2 (dash-dotted blue line, lower panel).