The enclosed mass (left) and circular velocity (right) for halo Aq-A (top panels) and halo Aq-D (bottom panels) with NFW fits to the circular velocity (blue lines). The red dashed curve shows the profile when we match the peak velocity. For an NFW the position of this maximum depends only on r_s and its magnitude only on M_s. The radial range plotted starts at the convergence radius (Power et al. 2003; Navarro et al. 2010) and extends up to r₂₀₀ (see Springel et al. 2008).